drivers/rtc/rtc-tegra.c: set irq name as device name

The irq name of tegra rtc shows as "rtc alarm" which actually does not
reflect the name related to driver.

Passing the device name to have the irq names with driver name.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Reviewed-by: Thierry Reding <thierry.reding@avionic-design.de>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Cc: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>