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-imx/eukrea_mbimxsd25-baseboard.c b/arch/arm/mach-imx/eukrea_mbimxsd25-baseboard.c
index 7cab720..cb705c2 100644
--- a/arch/arm/mach-imx/eukrea_mbimxsd25-baseboard.c
+++ b/arch/arm/mach-imx/eukrea_mbimxsd25-baseboard.c
@@ -37,7 +37,7 @@
 
 #include "devices-imx25.h"
 
-static struct pad_desc eukrea_mbimxsd_pads[] = {
+static iomux_v3_cfg_t eukrea_mbimxsd_pads[] = {
 	/* LCD */
 	MX25_PAD_LD0__LD0,
 	MX25_PAD_LD1__LD1,