lib: skip route-map optimization if !AF_INET(6)

lib: skip route-map optimization if !AF_INET(6)

Currently we unconditionally send a prefix through the optimized
route-map codepath if the v4 and v6 LPM tables have been allocated and
optimization has not been disabled.
However prefixes from address-families that are not IPv4/IPv6 unicast
always fail the optimized route-map index lookup, because they occur on
an LPM tree that is IPv4 or IPv6 specific.
e.g.
Even if you have an empty permit route-map clause, Type-3 EVPN routes
are always denied:
```
--config
route-map soo-foo permit 10

--logs
2023/02/17 19:38:42 BGP: [KZK58-6T4Y6] No best match sequence for pfx: [3]:[0]:[32]:[2.2.2.2] in route-map: soo-foo, result: no match
2023/02/17 19:38:42 BGP: [H5AW4-JFYQC] Route-map: soo-foo, prefix: [3]:[0]:[32]:[2.2.2.2], result: deny
```

There is some existing code that creates an AF_INET/AF_INET6 prefix
using the IP/prefix information from a Type-2/5 EVPN route, which
allowed only these two route-types to successfully attempt an LPM lookup
in the route-map optimization trees via the converted prefix.

This commit does 3 things:
1) Reverts to non-optimized route-map lookup for prefixes that are not
   AF_INET or AF_INET6.
2) Cleans up the route-map code so that the AF check is part of the
   index lookup + the EVPN RT-2/5 -> AF_INET/6 prefix conversion occurs
   outside the index lookup.
3) Adds "debug route-map detail" logs to indicate when we attempt to
   convert an AF_EVPN prefix into an AF_INET/6 prefix + when we fallback
   to a non-optimized lookup.

Additional functionality for optimized lookups of prefixes from other
address-families can be added prior to the index lookup, similar to how
the existing EVPN conversion works today.

New behavior:
```
2023/02/17 21:44:27 BGP: [WYP1M-NE4SY] Converted EVPN prefix [5]:[0]:[32]:[192.0.2.7] into 192.0.2.7/32 for optimized route-map lookup
2023/02/17 21:44:27 BGP: [MT1SJ-WEJQ1] Best match route-map: soo-foo, sequence: 10 for pfx: 192.0.2.7/32, result: match
2023/02/17 21:44:27 BGP: [H5AW4-JFYQC] Route-map: soo-foo, prefix: 192.0.2.7/32, result: permit

2023/02/17 21:44:27 BGP: [WYP1M-NE4SY] Converted EVPN prefix [2]:[0]:[48]:[aa:bb:cc:00:22:22]:[32]:[20.0.0.2] into 20.0.0.2/32 for optimized route-map lookup
2023/02/17 21:44:27 BGP: [MT1SJ-WEJQ1] Best match route-map: soo-foo, sequence: 10 for pfx: 20.0.0.2/32, result: match
2023/02/17 21:44:27 BGP: [H5AW4-JFYQC] Route-map: soo-foo, prefix: 20.0.0.2/32, result: permit

2023/02/17 21:44:27 BGP: [KHG7H-RH4PN] Unable to convert EVPN prefix [3]:[0]:[32]:[2.2.2.2] into IPv4/IPv6 prefix. Falling back to non-optimized route-map lookup
2023/02/17 21:44:27 BGP: [MT1SJ-WEJQ1] Best match route-map: soo-foo, sequence: 10 for pfx: [3]:[0]:[32]:[2.2.2.2], result: match
2023/02/17 21:44:27 BGP: [H5AW4-JFYQC] Route-map: soo-foo, prefix: [3]:[0]:[32]:[2.2.2.2], result: permit
```

Signed-off-by: Trey Aspelund <taspelund@nvidia.com>