Remove the WITNESS debug code from _STOPEVENT. It has pointed out a

problem, but the spamage of consoles is really bad.  Until we can get
this to be less chatty, disable it so people can boot.  The badness of
the spamage is worse than the badness that it reports :-(.  Once the
underlying problems have been fixed, it can be reenabled.

Approved by: kken, markm, rwatson, grog, murray

sys/sys/proc.h

@@ -729,8 +729,6 @@ MALLOC_DECLARE(M_ZOMBIE);
 } while (0)
 #define	_STOPEVENT(p, e, v) do {					\
 	PROC_LOCK_ASSERT(p, MA_OWNED);					\
-	WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, &p->p_mtx.mtx_object, \
-	    "checking stopevent %d", (e));				\
 	if ((p)->p_stops & (e))						\
 		stopevent((p), (e), (v));				\
 } while (0)