Fixed Bug 8121

Would reject buyingstores on @at, fixed (unlike vendings, buying stores are not able to survive restarts at this time, should be added soon)
http://hercules.ws/board/tracker/issue-8121-buyingstore-use-commend-autotrade-error/

Signed-off-by: shennetsind <ind@henn.et>

src/map/atcommand.c

@@ -5484,7 +5484,14 @@ ACMD(autotrade) {
 		int timeout = atoi(message);
 		status->change_start(NULL,&sd->bl, SC_AUTOTRADE, 10000, 0, 0, 0, 0, ((timeout > 0) ? min(timeout,battle_config.at_timeout) : battle_config.at_timeout) * 60000, 0);
 	}
-
+
+	/* currently standalones are not supporting buyingstores, so we rely on the previous method */
+	if( sd->state.buyingstore ) {
+		clif->authfail_fd(fd, 15);
+		return true;
+	}
+
+
 	clif->chsys_quit(sd);
 
 	clif->authfail_fd(sd->fd, 15);