ARM: i.MX IOMUX-V3 replace struct pad_desc with bitmapped cookie

The following patch is a first step to convert the 'struct pad_desc'
to a bitmapped cookie to facilitate adding platform specific pullup or
drive strength definitions to existing pad definitions without need to
rewrite the complete pad def.

The patch wraps 'struct pad_desc' in an opaque data type and
introduces macros to access the individual members.
This patch does not constitute any functional change!

Signed-off-by: Lothar Waßmann <LW@KARO-electronics.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
diff --git a/arch/arm/mach-mx5/board-mx51_efikamx.c b/arch/arm/mach-mx5/board-mx51_efikamx.c
index 6e623bd..1b1d4f1 100644
--- a/arch/arm/mach-mx5/board-mx51_efikamx.c
+++ b/arch/arm/mach-mx5/board-mx51_efikamx.c
@@ -39,7 +39,7 @@
 
 #define	MX51_USB_PLL_DIV_24_MHZ	0x01
 
-static struct pad_desc mx51efikamx_pads[] = {
+static iomux_v3_cfg_t mx51efikamx_pads[] = {
 	/* UART1 */
 	MX51_PAD_UART1_RXD__UART1_RXD,
 	MX51_PAD_UART1_TXD__UART1_TXD,