Currently only opt_compat.h is included by the mps(4) driver. Also

enable /dev/mps0, which was missing from my previous patches enabling
f/w upload and download.

opt_compat.h issue noticed by scottl.

sys/dev/mps/mps.c

@@ -924,7 +924,10 @@ mps_attach(struct mps_softc *sc)
 	/* Attach the subsystems so they can prepare their event masks. */
 	/* XXX Should be dynamic so that IM/IR and user modules can attach */
 	if (((error = mps_attach_log(sc)) != 0) ||
-	    ((error = mps_attach_sas(sc)) != 0)) {
+	    ((error = mps_attach_sas(sc)) != 0) ||
+	    ((error = mps_attach_user(sc)) != 0)) {
+		mps_printf(sc, "%s failed to attach all subsystems: error %d\n",
+		    __func__, error);
 		mps_free(sc);
 		return (error);
 	}

sys/modules/mps/Makefile

@@ -4,7 +4,7 @@
 
 KMOD=	mps
 SRCS=	mps_pci.c mps.c mps_sas.c mps_table.c mps_user.c
-SRCS+=	opt_mps.h opt_cam.h
+SRCS+=	opt_compat.h
 SRCS+=	device_if.h bus_if.h pci_if.h
 
 #CFLAGS += -DMPS_DEBUG