arm: dts: omap3-gta04a4: accelerometer irq fix

Fix typo in pinctrl. It did only work because the bootloader
seems to have initialized it.

Fixes: ee327111 ("ARM: dts: omap3-gta04: Define and use bma180 irq pin")
Signed-off-by: Andreas Kemnade <andreas@kemnade.info>
Signed-off-by: Tony Lindgren <tony@atomide.com>