arm: at91/spl: atmel_sfr: move saic redirect to separate file

To make saic redirect code sharing with other SoCs, move the
saic redirect code from SAMA5D4 particular file,
mach-at91/armv7/sama5d4_devices.c to a separate file,
mach-at91/atmel_sfr.c

Move ATMEL_SFR_AICREDIR_KEY definition to sama5d4.h, because each
SoC has its own value.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Reviewed-by: Andreas Bießmann <andreas.devel@googlemail.com>
diff --git a/arch/arm/mach-at91/include/mach/sama5d4.h b/arch/arm/mach-at91/include/mach/sama5d4.h
index 449cf0e..90085da 100644
--- a/arch/arm/mach-at91/include/mach/sama5d4.h
+++ b/arch/arm/mach-at91/include/mach/sama5d4.h
@@ -204,6 +204,9 @@
 #define H32MX_SLAVE_USB			5	/* USB Device & Host */
 #define H32MX_SLAVE_SMD			6	/* Soft Modem (SMD) */
 
+/* AICREDIR Unlock Key */
+#define ATMEL_SFR_AICREDIR_KEY		0x5F67B102
+
 /* sama5d4 series chip id definitions */
 #define ARCH_ID_SAMA5D4		0x8a5c07c0
 #define ARCH_EXID_SAMA5D41	0x00000001