tegra: make local functions static

Signed-off-by: Jeroen Hofstee <jeroen@myspectrum.nl>
diff --git a/board/nvidia/common/emc.c b/board/nvidia/common/emc.c
index 8124f8a..8c62f36 100644
--- a/board/nvidia/common/emc.c
+++ b/board/nvidia/common/emc.c
@@ -5,6 +5,7 @@
  */
 
 #include <common.h>
+#include "emc.h"
 #include <asm/io.h>
 #include <asm/arch/clock.h>
 #include <asm/arch/emc.h>