pbx_builtins: Corrects SayNumber warning

Previously, SayNumber always emitted a warning if the caller hung up
during execution. Usually this isn't correct, so check if the channel
hung up and, if so, don't emit a warning.

ASTERISK-29475

Change-Id: Ieea4a67301c6ea83bbc7690c1d4808d79a704594

main/pbx_builtins.c

@@ -1299,7 +1299,7 @@ static int pbx_builtin_saynumber(struct ast_channel *chan, const char *data)
 
 	res = ast_say_number(chan, number_val, interrupt ? AST_DIGIT_ANY : "", ast_channel_language(chan), options);
 
-	if (res < 0) {
+	if (res < 0 && !ast_check_hangup_locked(chan)) {
 		ast_log(LOG_WARNING, "We were unable to say the number %s, is it too large?\n", tmp);
 	}