fixes solaris segfault on dial with verbosity >= 3

(closes issue #16193)
Reported by: asgaroth
Patches:
      bug_16193_1.4.21.2_vers.diff uploaded by snuffy (license 35)
Tested by: asgaroth, snuffy



git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@231235 65c4cc65-6c06-0410-ace0-fbb531ad65f3

apps/app_dial.c

@@ -1044,10 +1044,10 @@ static int dial_exec_full(struct ast_channel *chan, void *data, struct ast_flags
 		warning_sound = S_OR(var, "timeleft");
 		
 		var = pbx_builtin_getvar_helper(chan,"LIMIT_TIMEOUT_FILE");
-		end_sound = S_OR(var, NULL);	/* XXX not much of a point in doing this! */
+		end_sound = S_OR(var, "");
 		
 		var = pbx_builtin_getvar_helper(chan,"LIMIT_CONNECT_FILE");
-		start_sound = S_OR(var, NULL);	/* XXX not much of a point in doing this! */
+		start_sound = S_OR(var, "");
 
 		/* undo effect of S(x) in case they are both used */
 		calldurationlimit = -1;