Conditionally acquire Giant based on debug.mpsafenet around entry points from if_re taskqueue and other potentially Giant-free spots.  If we don't do this, Giant may not be held entering KAME IPSEC, etc.
Conditionally acquire Giant based on debug.mpsafenet around entry points
from if_re taskqueue and other potentially Giant-free spots.  If we don't
do this, Giant may not be held entering KAME IPSEC, etc.

This problem appeared in FreeBSD 6.2 as a result of a move to fast
interrupts, and does not exist in 7.x due to not having debug.mpsafenet.

PR:		118719
Reported by:	Dan Lukes <dan at obluda dot cz>
Reviwed by:	yongari

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase