Clarify comment regarding what gotmsg() is for

src/mod/irc.mod/chan.c

@@ -3218,7 +3218,7 @@ static int gotquit(char *from, char *msg)
   return 0;
 }
 
-/* Got a private message.
+/* Got a channel message.
  */
 static int gotmsg(char *from, char *msg)
 {