Allow h264pred_init_arm.c to compile.

SOB: Bill Pringlemeir <bpringlemeir@yahoo.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/arm/h264pred_init_arm.c

@@ -74,7 +74,7 @@ static void ff_h264_pred_init_neon(H264PredContext *h, int codec_id, const int b
         h->pred16x16[PLANE_PRED8x8  ] = ff_pred16x16_plane_neon;
 }
 
-void ff_h264_pred_init_arm(H264PredContext *h, int codec_id, bit_depth)
+void ff_h264_pred_init_arm(H264PredContext *h, int codec_id, const int bit_depth)
 {
     if (HAVE_NEON)    ff_h264_pred_init_neon(h, codec_id, bit_depth);
 }