efi: rtc-efi: Export platform:rtc-efi as module alias

When the rtc-efi driver is built as a module, we already register the
EFI rtc as a platform device if UEFI Runtime Services are enabled.
To wire it up to udev, and let the module be loaded automatically, we
need to export the 'platform:rtc-efi' alias from the module.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Mark Salter <msalter@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
diff --git a/drivers/rtc/rtc-efi.c b/drivers/rtc/rtc-efi.c
index 8225b89..59a55e7 100644
--- a/drivers/rtc/rtc-efi.c
+++ b/drivers/rtc/rtc-efi.c
@@ -235,3 +235,4 @@
 MODULE_AUTHOR("dann frazier <dannf@hp.com>");
 MODULE_LICENSE("GPL");
 MODULE_DESCRIPTION("EFI RTC driver");
+MODULE_ALIAS("platform:rtc-efi");