Remove reference to non-existent help file

(closes issue #15427)
 Reported by: brushtyler
 Patches: 
       app_voicemail.c.diff uploaded by brushtyler (license 821)


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@206185 65c4cc65-6c06-0410-ace0-fbb531ad65f3

apps/app_voicemail.c

@@ -8311,10 +8311,7 @@ static int vm_instructions_en(struct ast_channel *chan, struct ast_vm_user *vmu,
 			}
 		}
 		if (!res) {
-			if (skipadvanced)
-				res = ast_play_and_wait(chan, "vm-helpexit-full");
-			else
-				res = ast_play_and_wait(chan, "vm-helpexit");
+			res = ast_play_and_wait(chan, "vm-helpexit");
 		}
 		if (!res)
 			res = ast_waitfordigit(chan, 6000);