KVM: x86: Drop NULL check on kvm_x86_ops.check_apicv_inhibit_reasons

Drop the useless NULL check on kvm_x86_ops.check_apicv_inhibit_reasons
when handling an APICv update, both VMX and SVM unconditionally implement
the helper and leave it non-NULL even if APICv is disabled at the module
level.  The latter is a moot point now that __kvm_request_apicv_update()
is called if and only if enable_apicv is true.

No functional change intended.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211208015236.1616697-26-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/kvm/x86.c

@@ -9679,8 +9679,7 @@ void __kvm_request_apicv_update(struct kvm *kvm, bool activate, ulong bit)
 
 	lockdep_assert_held_write(&kvm->arch.apicv_update_lock);
 
-	if (!kvm_x86_ops.check_apicv_inhibit_reasons ||
-	    !static_call(kvm_x86_check_apicv_inhibit_reasons)(bit))
+	if (!static_call(kvm_x86_check_apicv_inhibit_reasons)(bit))
 		return;
 
 	old = new = kvm->arch.apicv_inhibit_reasons;