lavc/dv: do not pass DVVideoContext to dv_calculate_mb_xy()

Pass the two variables needed from it directly.

This is done in preparation to splitting DVVideoContext.

libavcodec/dv.h

@@ -107,7 +107,8 @@ static inline int dv_work_pool_size(const AVDVProfile *d)
     return size;
 }
 
-static inline void dv_calculate_mb_xy(const DVVideoContext *s,
+static inline void dv_calculate_mb_xy(const AVDVProfile *sys,
+                                      const uint8_t *buf,
                                       const DVwork_chunk *work_chunk,
                                       int m, int *mb_x, int *mb_y)
 {
@@ -116,7 +117,7 @@ static inline void dv_calculate_mb_xy(const DVVideoContext *s,
 
     /* We work with 720p frames split in half.
      * The odd half-frame (chan == 2,3) is displaced :-( */
-    if (s->sys->height == 720 && !(s->buf[1] & 0x0C))
+    if (sys->height == 720 && !(buf[1] & 0x0C))
         /* shifting the Y coordinate down by 72/2 macro blocks */
         *mb_y -= (*mb_y > 17) ? 18 : -72;
 }

libavcodec/dvdec.c

@@ -533,7 +533,7 @@ retry:
     block = &sblock[0][0];
     mb    = mb_data;
     for (mb_index = 0; mb_index < 5; mb_index++) {
-        dv_calculate_mb_xy(s, work_chunk, mb_index, &mb_x, &mb_y);
+        dv_calculate_mb_xy(s->sys, s->buf, work_chunk, mb_index, &mb_x, &mb_y);
 
         /* idct_put'ting luminance */
         if ((s->sys->pix_fmt == AV_PIX_FMT_YUV420P)                      ||

libavcodec/dvenc.c

@@ -873,7 +873,7 @@ static int dv_encode_video_segment(AVCodecContext *avctx, void *arg)
     p = dif = &s->buf[work_chunk->buf_offset * 80];
     enc_blk = &enc_blks[0];
     for (mb_index = 0; mb_index < 5; mb_index++) {
-        dv_calculate_mb_xy(s, work_chunk, mb_index, &mb_x, &mb_y);
+        dv_calculate_mb_xy(s->sys, s->buf, work_chunk, mb_index, &mb_x, &mb_y);
 
         qnos[mb_index] = DV_PROFILE_IS_HD(s->sys) ? 1 : 15;