OMAP3: Correct name of omap34xx_gpios when using DM_GPIO

The name of the gpio bank under DM_GPIO appear to be a copy-paste error.
This changes the name of the gpio bank from am33xx_gpios to omap34xx_gpios.

Signed-off-by: Adam Ford <aford173@gmail.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/arch/arm/mach-omap2/omap3/board.c b/arch/arm/mach-omap2/omap3/board.c
index f1436fb..01df579 100644
--- a/arch/arm/mach-omap2/omap3/board.c
+++ b/arch/arm/mach-omap2/omap3/board.c
@@ -46,7 +46,7 @@
 	{ 5, OMAP34XX_GPIO6_BASE },
 };
 
-U_BOOT_DEVICES(am33xx_gpios) = {
+U_BOOT_DEVICES(omap34xx_gpios) = {
 	{ "gpio_omap", &omap34xx_gpio[0] },
 	{ "gpio_omap", &omap34xx_gpio[1] },
 	{ "gpio_omap", &omap34xx_gpio[2] },