Resolve FORWARD_NULL static analysis warnings

This resolves core findings from ASTERISK-19650 numbers 0-2, 6, 7, 9-11, 14-20,
22-24, 28, 30-32, 34-36, 42-56, 82-84, 87, 89-90, 93-102, 104, 105, 109-111,
and 115. Finding numbers 26, 33, and 29 were already resolved.  Those skipped
were either extended/deprecated or in areas of code that shouldn't be
disturbed.

(Closes issue ASTERISK-19650)


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.8@366167 65c4cc65-6c06-0410-ace0-fbb531ad65f3

main/event.c

@@ -1281,8 +1281,9 @@ struct ast_event *ast_event_new(enum ast_event_type type, ...)
 			break;
 		}
 
+		/* realloc inside one of the append functions failed */
 		if (!event) {
-			break;
+			return NULL;
 		}
 	}