KVM: x86: mmu: do not use return to tail-call functions that return void

This is, pedantically, not valid C.  It also looks weird.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/kvm/mmu.c

@@ -3900,11 +3900,11 @@ static void init_kvm_nested_mmu(struct kvm_vcpu *vcpu)
 static void init_kvm_mmu(struct kvm_vcpu *vcpu)
 {
 	if (mmu_is_nested(vcpu))
-		return init_kvm_nested_mmu(vcpu);
+		init_kvm_nested_mmu(vcpu);
 	else if (tdp_enabled)
-		return init_kvm_tdp_mmu(vcpu);
+		init_kvm_tdp_mmu(vcpu);
 	else
-		return init_kvm_softmmu(vcpu);
+		init_kvm_softmmu(vcpu);
 }
 
 void kvm_mmu_reset_context(struct kvm_vcpu *vcpu)