KVM: arm64: selftests: Allocate vcpus with correct size

vcpus array contains pointers to struct kvm_vcpu {}. It is way overkill
to allocate the array with (nr_cpus * sizeof(struct kvm_vcpu)). Fix the
allocation by using the correct size.

Signed-off-by: Zenghui Yu <zenghui.yu@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>

Author: Zenghui Yu

tools/testing/selftests/kvm/arm64/vgic_lpi_stress.c

@@ -331,7 +331,7 @@ static void setup_vm(void)
 {
 	int i;
 
-	vcpus = malloc(test_data.nr_cpus * sizeof(struct kvm_vcpu));
+	vcpus = malloc(test_data.nr_cpus * sizeof(struct kvm_vcpu *));
 	TEST_ASSERT(vcpus, "Failed to allocate vCPU array");
 
 	vm = vm_create_with_vcpus(test_data.nr_cpus, guest_code, vcpus);