Fix crash in app_voicemail related to message counting.

We were passing a 'struct inprocess **' and treating it like a 'struct inprocess *'
causing a segfault.

(closes issue #16921)
Reported by: whardier
Patches:
      20100301_issue16921.patch uploaded by seanbright (license 71)
Tested by: whardier


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@249671 65c4cc65-6c06-0410-ace0-fbb531ad65f3

apps/app_voicemail.c

@@ -439,7 +439,7 @@ static int inprocess_count(const char *context, const char *mailbox, int delta)
 	strcpy(arg->mailbox, mailbox); /* SAFE */
 	strcpy(arg->context, context); /* SAFE */
 	ao2_lock(inprocess_container);
-	if ((i = ao2_find(inprocess_container, &arg, 0))) {
+	if ((i = ao2_find(inprocess_container, arg, 0))) {
 		int ret = ast_atomic_fetchadd_int(&i->count, delta);
 		ao2_unlock(inprocess_container);
 		ao2_ref(i, -1);