selftests/kvm: fix compilation on non-x86_64 platforms

MEM_REGION_SLOT and MEM_REGION_GPA are not really needed in
test_invalid_memory_region_flags; the VM never runs and there are no
other slots, so it is okay to use slot 0 and place it at address
zero. This fixes compilation on architectures that do not
define them.

Fixes: 5d74316466f4 ("KVM: selftests: Add a memory region subtest to validate invalid flags")
Signed-off-by: Paolo Bonzini <[e-mail]>

tools/testing/selftests/kvm/guest_memfd_test.c

···
 	}
 
 	for (flag = 0; flag; flag <<= 1) {
-		uint64_t bit;
-
 		fd = __vm_create_guest_memfd(vm, page_size, flag);
 		TEST_ASSERT(fd == -1 && errno == EINVAL,
 			    "guest_memfd() with flag '0x%lx' should fail with EINVAL",

tools/testing/selftests/kvm/set_memory_region_test.c

···
 		if ((supported_flags & BIT(i)) && !(v2_only_flags & BIT(i)))
 			continue;
 
-		r = __vm_set_user_memory_region(vm, MEM_REGION_SLOT, BIT(i),
-						MEM_REGION_GPA, MEM_REGION_SIZE, NULL);
+		r = __vm_set_user_memory_region(vm, 0, BIT(i),
+						0, MEM_REGION_SIZE, NULL);
 
 		TEST_ASSERT(r && errno == EINVAL,
 			    "KVM_SET_USER_MEMORY_REGION should have failed on v2 only flag 0x%lx", BIT(i));
···
 		if (supported_flags & BIT(i))
 			continue;
 
-		r = __vm_set_user_memory_region2(vm, MEM_REGION_SLOT, BIT(i),
-						 MEM_REGION_GPA, MEM_REGION_SIZE, NULL, 0, 0);
+		r = __vm_set_user_memory_region2(vm, 0, BIT(i),
+						 0, MEM_REGION_SIZE, NULL, 0, 0);
 		TEST_ASSERT(r && errno == EINVAL,
 			    "KVM_SET_USER_MEMORY_REGION2 should have failed on unsupported flag 0x%lx", BIT(i));
 	}
 
 	if (supported_flags & KVM_MEM_GUEST_MEMFD) {
-		r = __vm_set_user_memory_region2(vm, MEM_REGION_SLOT,
+		r = __vm_set_user_memory_region2(vm, 0,
 						 KVM_MEM_LOG_DIRTY_PAGES | KVM_MEM_GUEST_MEMFD,
-						 MEM_REGION_GPA, MEM_REGION_SIZE, NULL, 0, 0);
+						 0, MEM_REGION_SIZE, NULL, 0, 0);
 		TEST_ASSERT(r && errno == EINVAL,
 			    "KVM_SET_USER_MEMORY_REGION2 should have failed, dirty logging private memory is unsupported");
 	}