bgpd: fix peer up message for loc-rib not sent

bgpd: fix peer up message for loc-rib not sent

At startup, there is no peer up message for loc-rib instance peer.
Instead, a global peer up message with address 0.0.0.0 is sent.

Such message is wrong, violates the RFC and should be dropped by
a strict collector. Actually, the peer type message sent is wrong,
and should be set to LOC-RIB peer type.

Fix this by changing the peer type of peer up message to either
loc-rib or global instance peer type.

Fixes: 035304c25a38 ("bgpd: bmp loc-rib peer up/down for vrfs")
Signed-off-by: Philippe Guibert <philippe.guibert@6wind.com>