KVM: x86: Remove a redundant guest cpuid check in kvm_set_cr4()

If !guest_cpuid_has(vcpu, X86_FEATURE_PCID), CR4.PCIDE would have been in
vcpu->arch.cr4_guest_rsvd_bits and failed earlier kvm_is_valid_cr4() check.
Remove this meaningless check.

Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Signed-off-by: Robert Hoo <robert.hu@linux.intel.com>
Fixes: 4683d75 ("KVM: x86: Supplement __cr4_reserved_bits() with X86_FEATURE_PCID check")
Link: https://lore.kernel.org/r/20230308072936.1293101-1-robert.hu@intel.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

Author: robert-hoo

arch/x86/kvm/x86.c

@@ -1196,9 +1196,6 @@ int kvm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
 		return 1;
 
 	if ((cr4 & X86_CR4_PCIDE) && !(old_cr4 & X86_CR4_PCIDE)) {
-		if (!guest_cpuid_has(vcpu, X86_FEATURE_PCID))
-			return 1;
-
 		/* PCID can not be enabled when cr3[11:0]!=000H or EFER.LMA=0 */
 		if ((kvm_read_cr3(vcpu) & X86_CR3_PCID_MASK) || !is_long_mode(vcpu))
 			return 1;