bgpd : aggregate-address memory leak fix

bgpd : aggregate-address memory leak fix

Memory leaks are observed in the cleanup code. When “no router bgp" is executed,
cleanup in that flow for aggregate-address command is not taken care.

fixes the below leak:
    --
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444:Direct leak of 152 byte(s) in 1 object(s) allocated from:
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444-    #0 0x7f163e911037 in __interceptor_calloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:154
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444-    #1 0x7f163e4b9259 in qcalloc lib/memory.c:105
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444-    #2 0x562bf42ebbd5 in bgp_aggregate_new bgpd/bgp_route.c:7239
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444-    #3 0x562bf42f14e8 in bgp_aggregate_set bgpd/bgp_route.c:8421
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444-    #4 0x562bf42f1e55 in aggregate_addressv6_magic bgpd/bgp_route.c:8592
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444-    #5 0x562bf42be3f5 in aggregate_addressv6 bgpd/bgp_route_clippy.c:341
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444-    #6 0x7f163e3f1e1b in cmd_execute_command_real lib/command.c:988
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444-    #7 0x7f163e3f219c in cmd_execute_command lib/command.c:1048
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444-    #8 0x7f163e3f2df4 in cmd_execute lib/command.c:1215
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444-    #9 0x7f163e5a2d73 in vty_command lib/vty.c:544
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444-    #10 0x7f163e5a79c8 in vty_execute lib/vty.c:1307
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444-    #11 0x7f163e5ad299 in vtysh_read lib/vty.c:2216
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444-    #12 0x7f163e593f16 in event_call lib/event.c:1995
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444-    #13 0x7f163e47c839 in frr_run lib/libfrr.c:1185
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444-    #14 0x562bf414e58d in main bgpd/bgp_main.c:505
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444-    #15 0x7f163de66d09 in __libc_start_main ../csu/libc-start.c:308
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444-
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444:Direct leak of 152 byte(s) in 1 object(s) allocated from:
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444-    #0 0x7f163e911037 in __interceptor_calloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:154
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444-    #1 0x7f163e4b9259 in qcalloc lib/memory.c:105
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444-    #2 0x562bf42ebbd5 in bgp_aggregate_new bgpd/bgp_route.c:7239
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444-    #3 0x562bf42f14e8 in bgp_aggregate_set bgpd/bgp_route.c:8421
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444-    #4 0x562bf42f1cde in aggregate_addressv4_magic bgpd/bgp_route.c:8543
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444-    #5 0x562bf42bd258 in aggregate_addressv4 bgpd/bgp_route_clippy.c:255
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444-    #6 0x7f163e3f1e1b in cmd_execute_command_real lib/command.c:988
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444-    #7 0x7f163e3f219c in cmd_execute_command lib/command.c:1048
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444-    #8 0x7f163e3f2df4 in cmd_execute lib/command.c:1215
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444-    #9 0x7f163e5a2d73 in vty_command lib/vty.c:544
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444-    #10 0x7f163e5a79c8 in vty_execute lib/vty.c:1307
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444-    #11 0x7f163e5ad299 in vtysh_read lib/vty.c:2216
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444-    #12 0x7f163e593f16 in event_call lib/event.c:1995
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444-    #13 0x7f163e47c839 in frr_run lib/libfrr.c:1185
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444-    #14 0x562bf414e58d in main bgpd/bgp_main.c:505
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444-    #15 0x7f163de66d09 in __libc_start_main ../csu/libc-start.c:308
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444-
    ./bgp_local_asn_dot.test_bgp_local_asn_dot_agg/r3.bgpd.asan.3410444-SUMMARY: AddressSanitizer: 304 byte(s) leaked in 2 allocation(s).

Signed-off-by: Samanvitha B Bhargav <bsamanvitha@vmware.com>