pcx: use init_get_bits8()

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/pcx.c

@@ -200,7 +200,7 @@ static int pcx_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
         GetBitContext s;
 
         for (y=0; y<h; y++) {
-            init_get_bits(&s, scanline, bytes_per_scanline<<3);
+            init_get_bits8(&s, scanline, bytes_per_scanline);
 
             pcx_rle_decode(&gb, scanline, bytes_per_scanline, compressed);