spi: pxa2xx: Use ACPI_COMPANION() instead of acpi_bus_get_device()

Get pointer to the struct acpi_device by using ACPI_COMPANION() macro. This
is more efficient than using ACPI_HANDLE() and acpi_bus_get_device().

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/drivers/spi/spi-pxa2xx.c b/drivers/spi/spi-pxa2xx.c
index 0e075db..aed9aab 100644
--- a/drivers/spi/spi-pxa2xx.c
+++ b/drivers/spi/spi-pxa2xx.c
@@ -1312,8 +1312,8 @@
 	const struct pci_device_id *pcidev_id = NULL;
 	int devid, type;
 
-	if (!ACPI_HANDLE(&pdev->dev) ||
-	    acpi_bus_get_device(ACPI_HANDLE(&pdev->dev), &adev))
+	adev = ACPI_COMPANION(&pdev->dev);
+	if (!adev)
 		return NULL;
 
 	if (dev_is_pci(pdev->dev.parent))