Use common function to set GPIOs for MX3 and MX5

The patch adds support for setting gpios to the
MX51 processor and change name to the corresponding
functions for MX31. In this way, it is possible to get rid
of nasty #ifdef switches related to the processor type.

Signed-off-by: Stefano Babic <sbabic@denx.de>
diff --git a/arch/arm/include/asm/arch-mx51/imx-regs.h b/arch/arm/include/asm/arch-mx51/imx-regs.h
index 3887d3c..0e3bc2a 100644
--- a/arch/arm/include/asm/arch-mx51/imx-regs.h
+++ b/arch/arm/include/asm/arch-mx51/imx-regs.h
@@ -256,6 +256,12 @@
 	u32	cswcr2;
 };
 
+/* GPIO Registers */
+struct gpio_regs {
+	u32	gpio_dr;
+	u32	gpio_dir;
+	u32	gpio_psr;
+};
 #endif /* __ASSEMBLER__*/
 
 #endif				/*  __ASM_ARCH_MXC_MX51_H__ */