ARM: imx: make all pin lists const and signed, move to .init where possible

Making the lists signed fixes sparse warnings like:

	arch/arm/mach-imx/mach-mx27_3ds.c:94:31: warning: incorrect type in argument 1 (different signedness)
	arch/arm/mach-imx/mach-mx27_3ds.c:94:31:    expected int const *pin_list
	arch/arm/mach-imx/mach-mx27_3ds.c:94:31:    got unsigned int static [toplevel] *<noident>

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
diff --git a/arch/arm/mach-imx/eukrea_mbimx27-baseboard.c b/arch/arm/mach-imx/eukrea_mbimx27-baseboard.c
index cb433ae..026263c 100644
--- a/arch/arm/mach-imx/eukrea_mbimx27-baseboard.c
+++ b/arch/arm/mach-imx/eukrea_mbimx27-baseboard.c
@@ -41,7 +41,7 @@
 #include "devices-imx27.h"
 #include "devices.h"
 
-static int eukrea_mbimx27_pins[] = {
+static const int eukrea_mbimx27_pins[] __initconst = {
 	/* UART2 */
 	PE3_PF_UART2_CTS,
 	PE4_PF_UART2_RTS,