imx: consolidate set_chipselect_size function

Move MX5 specific set_chipselect_size function into generic i.MX part,
such that MX6 based boards are able to use this function as well.

While doing this the iomuxc gpr member needed to be consolidated between
MX5 and MX6.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
diff --git a/arch/arm/include/asm/arch-mx5/imx-regs.h b/arch/arm/include/asm/arch-mx5/imx-regs.h
index 054c680..f059d0f 100644
--- a/arch/arm/include/asm/arch-mx5/imx-regs.h
+++ b/arch/arm/include/asm/arch-mx5/imx-regs.h
@@ -202,11 +202,6 @@
  */
 #define WBED		1
 
-#define CS0_128					0
-#define CS0_64M_CS1_64M				1
-#define CS0_64M_CS1_32M_CS2_32M			2
-#define CS0_32M_CS1_32M_CS2_32M_CS3_32M		3
-
 /*
  * CSPI register definitions
  */
@@ -414,8 +409,7 @@
 
 #if defined(CONFIG_MX51)
 struct iomuxc {
-	u32	gpr0;
-	u32	gpr1;
+	u32	gpr[2];
 	u32	omux0;
 	u32	omux1;
 	u32	omux2;
@@ -424,9 +418,7 @@
 };
 #elif defined(CONFIG_MX53)
 struct iomuxc {
-	u32	gpr0;
-	u32	gpr1;
-	u32	gpr2;
+	u32	gpr[3];
 	u32	omux0;
 	u32	omux1;
 	u32	omux2;