OvmfPkg/PlatformPei: program MSR_IA32_FEATURE_CONTROL from fw_cfg

OvmfPkg/PlatformPei: program MSR_IA32_FEATURE_CONTROL from fw_cfg

Under certain circumstances, QEMU exposes the "etc/msr_feature_control"
fw_cfg file, with a 64-bit little endian value. The firmware is supposed
to write this value to MSR_IA32_FEATURE_CONTROL (0x3a), on all processors,
on the normal and the S3 resume boot paths.

Utilize EFI_PEI_MPSERVICES_PPI to implement this feature.

Cc: Jeff Fan <jeff.fan@intel.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Michael Kinney <michael.d.kinney@intel.com>
Fixes: https://github.com/tianocore/edk2/issues/97
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jeff Fan <jeff.fan@intel.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>