usb: typec: ucsi: acpi: fix a NULL vs IS_ERR() check in probe

The devm_memremap() function never returns NULL.  It returns error
pointers.

Fixes: cdc3d2ab ("usb: typec: ucsi: acpi: Map the mailbox with memremap()")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/usb/typec/ucsi/ucsi_acpi.c

@@ -133,8 +133,8 @@ static int ucsi_acpi_probe(struct platform_device *pdev)
 	}
 
 	ua->base = devm_memremap(&pdev->dev, res->start, resource_size(res), MEMREMAP_WB);
-	if (!ua->base)
-		return -ENOMEM;
+	if (IS_ERR(ua->base))
+		return PTR_ERR(ua->base);
 
 	ret = guid_parse(UCSI_DSM_UUID, &ua->guid);
 	if (ret)