cpu/intel: add PC10 residency counter MSR

This MSR will be used in the follow-up changes.

Change-Id: Ia6f74861502d4a9f872b2bbbab2e5f1925a14c4d
Signed-off-by: Michael Niewöhner <foss@mniewoehner.de>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/49044
Reviewed-by: Lance Zhao
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/include/cpu/intel/msr.h

@@ -14,4 +14,6 @@
 
 #define MSR_PLATFORM_INFO	0xce
 
+#define MSR_PKG_C10_RESIDENCY	0x632
+
 #endif /* CPU_INTEL_MSR_H */