gpio: davinci: Do not clear the bank intr enable bit in save_context

The interrupt enable bits might be set if we want to use the GPIO as
wakeup source. Clearing this will mean disabling of interrupts in the GPIO
banks that we may want to wakeup from.
Thus remove the line that was clearing this bit from the driver's save
context function.

Cc: Devarsh Thakkar <devarsht@ti.com>
Fixes: 0651a730 ("gpio: davinci: Add support for system suspend/resume PM")
Signed-off-by: Dhruva Gole <d-gole@ti.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Keerthy <j-keerthy@ti.com>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>