[Blackfin] arch: declare list of peripherals as const since we dont modify the incoming array

Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>

diff --git a/include/asm-blackfin/portmux.h b/include/asm-blackfin/portmux.h
index 0d3f650..0807b28 100644
--- a/include/asm-blackfin/portmux.h
+++ b/include/asm-blackfin/portmux.h
@@ -17,8 +17,8 @@
 
 int peripheral_request(unsigned short per, const char *label);
 void peripheral_free(unsigned short per);
-int peripheral_request_list(unsigned short per[], const char *label);
-void peripheral_free_list(unsigned short per[]);
+int peripheral_request_list(const unsigned short per[], const char *label);
+void peripheral_free_list(const unsigned short per[]);
 
 #include <asm/gpio.h>
 #include <asm/mach/portmux.h>