kvm: x86: Cleanup vcpu->arch.guest_xstate_size

vcpu->arch.guest_xstate_size lost its only user since commit df1daba7
("KVM: x86: support XSAVES usage in the host"), so clean it up.
Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Message-Id: <20200429154312.1411-1-xiaoyao.li@intel.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/include/asm/kvm_host.h

@@ -657,7 +657,6 @@ struct kvm_vcpu_arch {
 
 	u64 xcr0;
 	u64 guest_supported_xcr0;
-	u32 guest_xstate_size;
 
 	struct kvm_pio_request pio;
 	void *pio_data;

arch/x86/kvm/cpuid.c

@@ -86,12 +86,10 @@ int kvm_update_cpuid(struct kvm_vcpu *vcpu)
 	best = kvm_find_cpuid_entry(vcpu, 0xD, 0);
 	if (!best) {
 		vcpu->arch.guest_supported_xcr0 = 0;
-		vcpu->arch.guest_xstate_size = XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET;
 	} else {
 		vcpu->arch.guest_supported_xcr0 =
 			(best->eax | ((u64)best->edx << 32)) & supported_xcr0;
-		vcpu->arch.guest_xstate_size = best->ebx =
-			xstate_required_size(vcpu->arch.xcr0, false);
+		best->ebx = xstate_required_size(vcpu->arch.xcr0, false);
 	}
 
 	best = kvm_find_cpuid_entry(vcpu, 0xD, 1);

arch/x86/kvm/x86.c

@@ -9387,8 +9387,6 @@ int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
 	}
 	fx_init(vcpu);
 
-	vcpu->arch.guest_xstate_size = XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET;
-
 	vcpu->arch.maxphyaddr = cpuid_query_maxphyaddr(vcpu);
 
 	vcpu->arch.pat = MSR_IA32_CR_PAT_DEFAULT;