Return correct error code if lock path fails. The recent changes to open_mailbox actually caused it to be fixed, but let's be consistent.

Reported by alecdavis in asterisk-dev.


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.6.2@294910 65c4cc65-6c06-0410-ace0-fbb531ad65f3

apps/app_voicemail.c

@@ -7409,7 +7409,7 @@ static int open_mailbox(struct vm_state *vms, struct ast_vm_user *vmu, int box)
 
 	if (vm_lock_path(vms->curdir)) {
 		ast_log(AST_LOG_ERROR, "Could not open mailbox %s:  mailbox is locked\n", vms->curdir);
-		return -1;
+		return ERROR_LOCK_PATH;
 	}
 
 	/* for local storage, checks directory for messages up to maxmsg limit */