bgpd: skip peers not activated for AFI/SAFI in bgp_gr_check_all_eors() (backport #22295)

[mergify]

bgp_gr_check_all_eors() walks every peer in bgp->peer and -- for any peer with PEER_STATUS_GR_WAIT_EOR set but no PEER_STATUS_EOR_RECEIVED -- splits into two code paths based on bgp->gr_multihop_peer_exists.

An existing !afc check filtered out peers that do not have this AFI/SAFI configured/activated, but it sat after the no-multihop-mix branch's early 'return false' -- so it was only ever reached when gr_multihop_peer_exists was true. The no-multihop-mix branch instead returned false on the first peer that lacked EOR_RECEIVED -- including peers that have no activated AF at all and are therefore physically incapable of ever sending an EOR for the AFI/SAFI in question.

In topologies where the BGP config defines neighbors that are never 'activate'd under any address family, this caused bgp_gr_check_all_eors() to return FALSE on every incoming EOR receipt, permanently blocking the GR fast-cancel path and forcing the deferral to always run to the select-defer-time safety-timer expiry.

Move the !afc check above the branch split so both branches see it; the post-split copy becomes unreachable and is removed.

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This is an automatic backport of pull request #22295 done by [Mergify](https://mergify.com).

[mergify]

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	both modified:   bgpd/bgp_fsm.c

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[greptile-apps]

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