UPSTREAM: soc/intel/skylake: Add config option for Kabylake

Currently there is no distinction between mainboards using
Skylake or Kabylake SoC, Add a config option for Kabylake
SoC to allow mainboards to explicitly select if they are
using it.

BUG=none
BRANCH=none
TEST=none

Change-Id: I1c0e5acebce9db7e06e2e320dbdf67d6c63061b7
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: 0700dca969
Original-Change-Id: Ie7960bd81f88a223894afe3115ddc0bc637e4be4
Original-Signed-off-by: Rizwan Qureshi <rizwan.qureshi@intel.com>
Original-Reviewed-on: https://review.coreboot.org/18312
Original-Tested-by: build bot (Jenkins)
Original-Reviewed-by: Furquan Shaikh <furquan@google.com>
Original-Reviewed-by: Martin Roth <martinroth@google.com>
Reviewed-on: https://chromium-review.googlesource.com/445124

src/soc/intel/skylake/Kconfig

@@ -3,6 +3,13 @@ config SOC_INTEL_SKYLAKE
 	help
 	  Intel Skylake support
 
+config SOC_INTEL_KABYLAKE
+	bool
+	default n
+	select SOC_INTEL_SKYLAKE
+	help
+	  Intel Kabylake support
+
 if SOC_INTEL_SKYLAKE
 
 config CPU_SPECIFIC_OPTIONS