ARM: OMAP1: Amstrad Delta: Fix wrong IRQ base in FIQ handler

Commit 384ebe1c, "gpio/omap: Add DT
support to GPIO driver", introduced dynamic IRQ numbering of OMAP GPIO
interrupts, breaking all IH_GPIO_BASE based IRQ number calculations.
This issue was corrected in the OMAP GPIO driver and the related header
file with commit 25db711d, "gpio/omap:
Fix IRQ handling for SPARSE_IRQ".

However, the Amstrad Delta FIQ handler, which replaces the gpio-omap
driver in serving GPIO interrupts on this board, still uses that
outdated method. Fix it.
Signed-off-by: Janusz Krzysztofik <jkrzyszt@tis.icnet.pl>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/mach-omap1/ams-delta-fiq.c

@@ -48,7 +48,7 @@ static irqreturn_t deferred_fiq(int irq, void *dev_id)
 	struct irq_chip *irq_chip = NULL;
 	int gpio, irq_num, fiq_count;
 
-	irq_desc = irq_to_desc(IH_GPIO_BASE);
+	irq_desc = irq_to_desc(gpio_to_irq(AMS_DELTA_GPIO_PIN_KEYBRD_CLK));
 	if (irq_desc)
 		irq_chip = irq_desc->irq_data.chip;