MD2 limits check hotfix

Fixing slight mistake made in merge request !132 (merged) that someone else spotted, no real explanation needed

src/hardware/hw_md2.c

@@ -791,7 +791,7 @@ void HWR_InitMD2(void)
md2_models[i].grpatch = NULL;
md2_models[i].skin = -1;
md2_models[i].notfound = true;
-		md2_models[s].error = false;
+		md2_models[i].error = false;
}
// read the md2.dat file