svq3: Drop unused function dctcoef_get()

libavcodec/svq3.c:627:29: warning: unused function 'dctcoef_get' [-Wunused-function]

libavcodec/svq3.c

@@ -622,11 +622,6 @@ static av_always_inline void hl_decode_mb_idct_luma(SVQ3Context *s,
     }
 }
 
-static av_always_inline int dctcoef_get(int16_t *mb, int index)
-{
-    return AV_RN16A(mb + index);
-}
-
 static av_always_inline void hl_decode_mb_predict_luma(SVQ3Context *s,
                                                        int mb_type,
                                                        const int *block_offset,