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-mx3/mach-cpuimx35.c b/arch/arm/mach-mx3/mach-cpuimx35.c
index dda1988..26ae90f 100644
--- a/arch/arm/mach-mx3/mach-cpuimx35.c
+++ b/arch/arm/mach-mx3/mach-cpuimx35.c
@@ -72,7 +72,7 @@
 	},
 };
 
-static struct pad_desc eukrea_cpuimx35_pads[] = {
+static iomux_v3_cfg_t eukrea_cpuimx35_pads[] = {
 	/* UART1 */
 	MX35_PAD_CTS1__UART1_CTS,
 	MX35_PAD_RTS1__UART1_RTS,