chan_local: Fix local_pvt ref leak in local_devicestate().

Regression introduced by ASTERISK-20390 fix.

(closes issue ASTERISK-20769)
Reported by: rmudgett
Tested by: rmudgett
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Merged revisions 376868 from http://svn.asterisk.org/svn/asterisk/branches/1.8
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Merged revisions 376869 from http://svn.asterisk.org/svn/asterisk/branches/10
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Merged revisions 376870 from http://svn.asterisk.org/svn/asterisk/branches/11


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@376871 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channels/chan_local.c

@@ -311,15 +311,20 @@ static int local_devicestate(const char *data)
 	res = AST_DEVICE_NOT_INUSE;
 
 	it = ao2_iterator_init(locals, 0);
-	while ((lp = ao2_iterator_next(&it)) && (res == AST_DEVICE_NOT_INUSE)) {
-		if (!strcmp(exten, lp->exten) && !strcmp(context, lp->context) && lp->owner) {
-			ao2_lock(lp);
-			if (ast_test_flag(lp, LOCAL_LAUNCHED_PBX)) {
-				res = AST_DEVICE_INUSE;
-			}
-			ao2_unlock(lp);
+	for (; (lp = ao2_iterator_next(&it)); ao2_ref(lp, -1)) {
+		int is_inuse;
+
+		ao2_lock(lp);
+		is_inuse = !strcmp(exten, lp->exten)
+			&& !strcmp(context, lp->context)
+			&& lp->owner
+			&& ast_test_flag(lp, LOCAL_LAUNCHED_PBX);
+		ao2_unlock(lp);
+		if (is_inuse) {
+			res = AST_DEVICE_INUSE;
+			ao2_ref(lp, -1);
+			break;
 		}
-		ao2_ref(lp, -1);
 	}
 	ao2_iterator_destroy(&it);