x86: kconfig: Imply ENABLE_MRC_CACHE in the platform Kconfig

Platform knows whether MRC cache is implemented, but using it can
be a choice of a specific board.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/x86/cpu/ivybridge/Kconfig b/arch/x86/cpu/ivybridge/Kconfig
index ed6b834..5df5e3a 100644
--- a/arch/x86/cpu/ivybridge/Kconfig
+++ b/arch/x86/cpu/ivybridge/Kconfig
@@ -9,6 +9,7 @@
 	bool
 	select CACHE_MRC_BIN if HAVE_MRC
 	imply HAVE_INTEL_ME
+	imply ENABLE_MRC_CACHE
 
 if NORTHBRIDGE_INTEL_IVYBRIDGE