gpio: pca953x: remove redundant variable and check in IRQ handler

gpio: pca953x: remove redundant variable and check in IRQ handler

We always will have at least one iteration of the loop due to pending
being guaranteed to be non-zero.  That is, we may remove extra variable
and check in the IRQ handler.

Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Andy Shevchenko <[email protected]>
Acked-by: Linus Walleij <[email protected]>
Cc: Bartosz Golaszewski <[email protected]>
Cc: Geert Uytterhoeven <[email protected]>
Cc: Marek Vasut <[email protected]>
Cc: Rasmus Villemoes <[email protected]>
Cc: Thomas Petazzoni <[email protected]>
Cc: William Breathitt Gray <[email protected]>
Cc: Yury Norov <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>