powerpc/powernv: remove FW_FEATURE_OPALv3 and just use FW_FEATURE_OPAL

Long ago, only in the lab, there was OPALv1 and OPALv2. Now there is
just OPALv3, with nobody ever expecting anything on pre-OPALv3 to
be cared about or supported by mainline kernels.

So, let's remove FW_FEATURE_OPALv3 and instead use FW_FEATURE_OPAL
exclusively.

Signed-off-by: Stewart Smith <stewart@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
diff --git a/drivers/cpufreq/powernv-cpufreq.c b/drivers/cpufreq/powernv-cpufreq.c
index cb50138..547890f 100644
--- a/drivers/cpufreq/powernv-cpufreq.c
+++ b/drivers/cpufreq/powernv-cpufreq.c
@@ -586,7 +586,7 @@
 	int rc = 0;
 
 	/* Don't probe on pseries (guest) platforms */
-	if (!firmware_has_feature(FW_FEATURE_OPALv3))
+	if (!firmware_has_feature(FW_FEATURE_OPAL))
 		return -ENODEV;
 
 	/* Discover pstates from device tree and init */