kprobes: Remove pointless BUG_ON() from disarming process

All aggr_probes at this line are already disarmed by
disable_kprobe() or checked by kprobe_disarmed().

So this BUG_ON() is pointless, remove it.
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: David S . Miller <davem@davemloft.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Naveen N . Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/153666115463.21306.8799008438116029806.stgit@devboxSigned-off-by: Ingo Molnar <mingo@kernel.org>

kernel/kprobes.c

@@ -1704,7 +1704,6 @@ static int __unregister_kprobe_top(struct kprobe *p)
 	return 0;
 
 disarmed:
-	BUG_ON(!kprobe_disarmed(ap));
 	hlist_del_rcu(&ap->hlist);
 	return 0;
 }