channels/chan_skinny: Fix compilation error introduced in f8e21a1adf

A typo in commit f8e21a1adf resulted in a compilation error in
chan_skinny. This patch fixes the typo.

ASTERISK-24917

Change-Id: Id7f4ad1fe948eb2408622e80c27936ce4516c33c

channels/chan_skinny.c

@@ -7545,7 +7545,7 @@ static void *skinny_session(void *data)
 				break;
 			}
 
-			eventmessage = letohl(req-e);
+			eventmessage = letohl(req->e);
 			if (eventmessage < 0) {
 				ast_log(LOG_ERROR, "Event Message is NULL from socket %d, This is bad\n", s->fd);
 				break;