soc/intel/common: Use SPR for backing up data way and eviction mask

soc/intel/common: Use SPR for backing up data way and eviction mask

This patch replaces the usage of GPR (General Purpose Registers) like
ECX and EBX for backing up data way and non-eviction mask with SPR
(Special Purpose Registers) EDI and ESI.

Purpose of this change is to ensure the safety while developers might
use ECX often while doing rdmsr/wrmsr rather than making use of EDI.

TEST=Able to boot JSL and TGL platform without any hang using eNEM.

Change-Id: I12e0cb7bb050e4f7b17ecf30108db335d1d82ab7
Signed-off-by: Subrata Banik <subrata.banik@intel.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/56161
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-by: Tim Wawrzynczak <twawrzynczak@chromium.org>
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>