linux-phytec-ti

msm: trout: add gpio_to_irq

trout has gpiolib support and interrupt support, but was
missing the gpio_to_irq function. This adds that functions
which should allow proper translation.

Signed-off-by: Daniel Walker <dwalker@codeaurora.org>
Signed-off-by: David Brown <davidb@codeaurora.org>