lib: Take ge/le into consideration when checking the prefix with the prefix-list

lib: Take ge/le into consideration when checking the prefix with the prefix-list

Without the fix:

```
show ip prefix-list test_1 10.20.30.96/27 first-match
 <no result>

show ip prefix-list test_2 192.168.1.2/32 first-match
 <no result>
```

With the fix:

```
ip prefix-list test_1 seq 10 permit 10.20.30.64/26 le 27
!
end
donatas# show ip prefix-list test_1 10.20.30.96/27
   seq 10 permit 10.20.30.64/26 le 27 (hit count: 1, refcount: 0)
donatas# show ip prefix-list test_1 10.20.30.64/27
   seq 10 permit 10.20.30.64/26 le 27 (hit count: 2, refcount: 0)
donatas# show ip prefix-list test_1 10.20.30.64/28
donatas# show ip prefix-list test_1 10.20.30.126/26
   seq 10 permit 10.20.30.64/26 le 27 (hit count: 3, refcount: 0)
donatas# show ip prefix-list test_1 10.20.30.126/30
donatas#
```

Signed-off-by: Donatas Abraitis <donatas@opensourcerouting.org>