ARM: OMAP1: ams-delta FIQ: don't use static GPIO numbers

With introduction of GPIO lookup tables to Amstrad Delta board init
file, semantics of symbols representing OMAP GPIO pins defined in
<mach/board-ams-delta.h> changed from statically assigned global GPIO
numbers to hardware pin numbers local to OMAP "gpio-0-15" chip.

This patch modifies deferred FIQ interrupt handler so it no longer uses
static GPIO numbers in favour of IRQ data descriptors obtained at FIQ
initialization time from descriptor of the GPIO chip with use of its
hardware pin numbers.  The chip descriptor is passed from the board
init file.

As a benefit, the deferred FIQ handler should work faster.

Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
[tony@atomide.com: removed duplicate gpiochip_match_by_label]
Signed-off-by: Tony Lindgren <tony@atomide.com>