avcodec/proresenc_kostya: remove redundant codebook assignments

This is already assigned at declaration.

libavcodec/proresenc_kostya.c

@@ -440,7 +440,6 @@ static void encode_dcs(PutBitContext *pb, int16_t *blocks,
     prev_dc = (blocks[0] - 0x4000) / scale;
     encode_vlc_codeword(pb, FIRST_DC_CB, MAKE_CODE(prev_dc));
     sign     = 0;
-    codebook = 3;
     blocks  += 64;
 
     for (i = 1; i < blocks_per_slice; i++, blocks += 64) {
@@ -675,7 +674,6 @@ static int estimate_dcs(int *error, int16_t *blocks, int blocks_per_slice,
     prev_dc  = (blocks[0] - 0x4000) / scale;
     bits     = estimate_vlc(FIRST_DC_CB, MAKE_CODE(prev_dc));
     sign     = 0;
-    codebook = 3;
     blocks  += 64;
     *error  += FFABS(blocks[0] - 0x4000) % scale;