spi: prefix modalias with "spi:"

This makes it consistent with other buses (platform, i2c, vio, ...).  I'm
not sure why we use the prefixes, but there must be a reason.

This was easy enough to do it, and I did it.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Dmitry Torokhov <dtor@mail.ru>
Cc: Samuel Ortiz <sameo@openedhand.com>
Cc: "John W. Linville" <linville@tuxdriver.com>
Acked-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/rtc/rtc-m41t94.c b/drivers/rtc/rtc-m41t94.c
index c3a18c5..c8c97a4 100644
--- a/drivers/rtc/rtc-m41t94.c
+++ b/drivers/rtc/rtc-m41t94.c
@@ -171,3 +171,4 @@
 MODULE_AUTHOR("Kim B. Heino <Kim.Heino@bluegiga.com>");
 MODULE_DESCRIPTION("Driver for ST M41T94 SPI RTC");
 MODULE_LICENSE("GPL");
+MODULE_ALIAS("spi:rtc-m41t94");