KVM: SVM: Don't check for assigned device(s) when activating AVIC

Don't short-circuit IRTE updating when (de)activating AVIC based on the
VM having assigned devices, as nothing prevents AVIC (de)activation from
racing with device (de)assignment.  And from a performance perspective,
bailing early when there is no assigned device doesn't add much, as
ir_list_lock will never be contended if there's no assigned device.

Link: https://lore.kernel.org/r/20250611224604.313496-47-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

Author: sean-jc

arch/x86/kvm/svm/avic.c

@@ -733,9 +733,6 @@ static int avic_set_pi_irte_mode(struct kvm_vcpu *vcpu, bool activate)
 	struct vcpu_svm *svm = to_svm(vcpu);
 	struct kvm_kernel_irqfd *irqfd;
 
-	if (!kvm_arch_has_assigned_device(vcpu->kvm))
-		return 0;
-
 	/*
 	 * Here, we go through the per-vcpu ir_list to update all existing
 	 * interrupt remapping table entry targeting this vcpu.