vfio: platform: Do not pass return buffer to ACPI _RST method

The ACPI _RST method has no return value, there's no need to pass a return
buffer to acpi_evaluate_object().

Fixes: d30daa33 ("vfio: platform: call _RST method when using ACPI")
Signed-off-by: Rafael Mendonca <rafaelmendsr@gmail.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Link: https://lore.kernel.org/r/20221018152825.891032-1-rafaelmendsr@gmail.comSigned-off-by: Alex Williamson <alex.williamson@redhat.com>

drivers/vfio/platform/vfio_platform_common.c

@@ -72,12 +72,11 @@ static int vfio_platform_acpi_call_reset(struct vfio_platform_device *vdev,
 				  const char **extra_dbg)
 {
 #ifdef CONFIG_ACPI
-	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 	struct device *dev = vdev->device;
 	acpi_handle handle = ACPI_HANDLE(dev);
 	acpi_status acpi_ret;
 
-	acpi_ret = acpi_evaluate_object(handle, "_RST", NULL, &buffer);
+	acpi_ret = acpi_evaluate_object(handle, "_RST", NULL, NULL);
 	if (ACPI_FAILURE(acpi_ret)) {
 		if (extra_dbg)
 			*extra_dbg = acpi_format_exception(acpi_ret);