Merge pull request #12854 from opensourcerouting/fix/bgp_withdraw_attr_not_used

bgpd: Drop struct attr from bgp_withdraw()

diff --cc bgpd/bgp_evpn.c
Simple merge

diff --cc bgpd/bgp_evpn_mh.c
Simple merge

diff --cc bgpd/bgp_mplsvpn.c
Simple merge

diff --cc bgpd/bgp_route.c
Simple merge

diff --cc bgpd/bgp_route.h
Simple merge