Fix autoconfiguration for accelerated drivers on sparc/sparc64. Currently

limited to sunffb; others will need to be added to bsd_sbus.c if we start
shipping them.

ok matthieu@, oga@

xserver/hw/xfree86/common/xf86AutoConfig.c

@@ -468,7 +468,7 @@ listPossibleVideoDrivers(char *matches[], int nmatches)
 	}
     }
 #endif
-#if defined(__sparc__) && !defined(__OpenBSD__)
+#if defined(__sparc__)
     {
 	char *sbusDriver = sparcDriverName();
 	if (sbusDriver)

xserver/hw/xfree86/os-support/bsd/bsd_sbus.c

@@ -190,3 +190,14 @@ void
 sparcPromClose(void)
 {
 }
+
+char *
+sparcDriverName(void)
+{
+	switch (sbusInfo.devId) {
+	case SBUS_DEVICE_FFB:
+		return "sunffb";
+	default:
+		return NULL;
+	}
+}