OvmfPkg/PlatformPei: remove mFeatureControlValue

Use PlatformInfoHob->FeatureControlValue instead.
OnMpServicesAvailable() will find PlatformInfoHob using
GetFirstGuidHob() and pass a pointer to the WriteFeatureControl
callback.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Tested-by: Tom Lendacky <thomas.lendacky@amd.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>

OvmfPkg/Include/Library/PlatformInitLib.h

@@ -48,6 +48,8 @@ typedef struct {
 
   UINT32               S3AcpiReservedMemoryBase;
   UINT32               S3AcpiReservedMemorySize;
+
+  UINT64               FeatureControlValue;
 } EFI_HOB_PLATFORM_INFO;
 #pragma pack()