coresight: Drop double check for ACPI companion device

acpi_dev_get_resources() does perform the NULL pointer check against
ACPI companion device which is given as function parameter. Thus,
there is no need to duplicate this check in the caller.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20200716175746.3338735-9-mathieu.poirier@linaro.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/hwtracing/coresight/coresight-stm.c

@@ -727,8 +727,6 @@ static int acpi_stm_get_stimulus_area(struct device *dev, struct resource *res)
 
 	struct acpi_device *adev = ACPI_COMPANION(dev);
 
-	if (!adev)
-		return -ENODEV;
 	rc = acpi_dev_get_resources(adev, &res_list, NULL, NULL);
 	if (rc < 0)
 		return rc;