Pull up following revision(s) (requested by ozaki-r in ticket #457):
sys/net/rtsock.c: revision 1.233-1.234, 1.236
Protect ifp returned from route_output_get_ifa surely
An ifp returned from route_output_get_ifa was supposed to be protected
by a returned ifa; if the ifa belongs to ifp, holding the ifa prevents
the ifp from being freed. However route_output_get_ifa can return an ifp
to which a returned ifa doesn't belong. So we need to take a reference
to a returning ifp separately.
--
Fix a bug that tries to psref_acquire ifa with a psref used before
This fixes ATF tests that started to fail by a recent change to psref.
--
Fix compile error (may be used uninitialized)
Hmm, __noinline had hidden this error.

(snj)