mmc: let tmio-mmc use dev_name() with request_irq()

Improve the /proc/interrupts output so the irq number can be mapped to
platform device on boards with multiple tmio_mmc instances.

Signed-off-by: Magnus Damm <damm@opensource.se>
Cc: <linux-mmc@vger.kernel.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>