linux: enable CONFIG_POWER8_CPU

Since we only build for LE now, there is no sense in building for POWER7,
as a POWER7 powernv LE kernel is something that will never, ever work.

Signed-off-by: Stewart Smith <stewart@linux.vnet.ibm.com>
diff --git a/openpower/configs/linux/skiroot_defconfig b/openpower/configs/linux/skiroot_defconfig
index 40081ba..ab0ea33 100644
--- a/openpower/configs/linux/skiroot_defconfig
+++ b/openpower/configs/linux/skiroot_defconfig
@@ -1,4 +1,5 @@
 CONFIG_PPC64=y
+CONFIG_POWER8_CPU=y
 CONFIG_ALTIVEC=y
 CONFIG_VSX=y
 CONFIG_SMP=y