cpu/intel/common: correct MSR for the Nominal Performance in CPPC

The "Nominal Performance" is not the same as the "Guaranteed
Performance", but is defined as the performance a processor can deliver
continously under ideal environmental conditions.

According to edk2, this is the "Maximum Non-Turbo Ratio", which needs to
be read from MSR_PLATFORM_INFO instead of IA32_HWP_CAPABILITIES.

Correct the entry in the CPPC package.

Test: dumped SSDT from Supermicro X11SSM-F and checked decompiled
version

Change-Id: Ic2c27fd3e14af18aa4101c0acd7a5ede15d1f3a9
Signed-off-by: Michael Niewöhner <foss@mniewoehner.de>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/46464
Reviewed-by: Subrata Banik <subrata.banik@intel.com>
Reviewed-by: Tim Wawrzynczak <twawrzynczak@chromium.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/include/cpu/intel/msr.h

@@ -12,4 +12,6 @@
 #define MSR_PIC_MSG_CONTROL	0x2e
 #define  TPR_UPDATES_DISABLE	(1 << 10)
 
+#define MSR_PLATFORM_INFO	0xce
+
 #endif /* CPU_INTEL_MSR_H */