decodframe: make local symbol static.

Change-Id: Id55f3cd3c2f5857dbfd78703452740dfd63cdf41

vp8/decoder/decodframe.c

diff --git a/vp8/decoder/decodframe.c b/vp8/decoder/decodframe.c
index 39ad8ab..9240529 100644
--- a/vp8/decoder/decodframe.c
+++ b/vp8/decoder/decodframe.c
@@ -95,7 +95,7 @@
   }
 }
 
-void mb_init_dequantizer(VP8D_COMP *pbi, MACROBLOCKD *xd) {
+static void mb_init_dequantizer(VP8D_COMP *pbi, MACROBLOCKD *xd) {
   int i;
   int QIndex;
   VP8_COMMON *const pc = &pbi->common;