Add gpio-keys kernel feature

Add a gpio-keys feature to be used with KERNEL_FEATURES.

Change-Id: I0f96b842a55b38eb573ad894f79ef4621b97e839
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>
diff --git a/common/recipes-kernel/linux/linux-obmc/phosphor-gpio-keys.scc b/common/recipes-kernel/linux/linux-obmc/phosphor-gpio-keys.scc
new file mode 100644
index 0000000..78961af
--- /dev/null
+++ b/common/recipes-kernel/linux/linux-obmc/phosphor-gpio-keys.scc
@@ -0,0 +1,2 @@
+define KFEATURE_DESCRIPTION "Enable gpio-keys"
+kconf non-hardware phosphor-gpio-keys.cfg