ARM: at91: sfr: convert to Kconfig

This converts the at91 sfr to Kconfig

Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
diff --git a/arch/arm/mach-at91/atmel_sfr.c b/arch/arm/mach-at91/atmel_sfr.c
index 2225115..07bd8ab 100644
--- a/arch/arm/mach-at91/atmel_sfr.c
+++ b/arch/arm/mach-at91/atmel_sfr.c
@@ -9,6 +9,7 @@
 #include <asm/io.h>
 #include <asm/arch/sama5_sfr.h>
 
+#if defined(CONFIG_SAMA5D2) || defined(CONFIG_SAMA5D4)
 void redirect_int_from_saic_to_aic(void)
 {
 	struct atmel_sfr *sfr = (struct atmel_sfr *)ATMEL_BASE_SFR;
@@ -26,3 +27,5 @@
 
 	writel(1, &sfr->l2cc_hramc);
 }
+#endif
+