kvm: x86: Add CPUID support for Intel AMX

mainline inclusion
from mainline-v5.17-rc1
commit 690a757d
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I5RQLJ


CVE: NA

Intel-SIG: commit 690a757d kvm: x86: Add CPUID support for Intel AMX.

--------------------------------

Extend CPUID emulation to support XFD, AMX_TILE, AMX_INT8 and
AMX_BF16. Adding those bits into kvm_cpu_caps finally activates all
previous logics in this series.

Hide XFD on 32bit host kernels. Otherwise it leads to a weird situation
where KVM tells userspace to migrate MSR_IA32_XFD and then rejects
attempts to read/write the MSR.

Signed-off-by: Jing Liu <jing2.liu@intel.com>
Signed-off-by: Yang Zhong <yang.zhong@intel.com>
Message-Id: <20220105123532.12586-17-yang.zhong@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Lin Wang <lin.x.wang@intel.com>