interplayvideo: fix av_dlog parameter type mismatch

libavcodec/interplayvideo.c:909:13: warning: format ‘%p’ expects argument of type ‘void *’, but argument 7 has type ‘GetByteContext’ [-Wformat]

libavcodec/interplayvideo.c

@@ -907,8 +907,9 @@ static void ipvideo_decode_opcodes(IpvideoContext *s)
         for (x = 0; x < s->avctx->width; x += 8) {
             opcode = get_bits(&gb, 4);
 
-            av_dlog(NULL, "  block @ (%3d, %3d): encoding 0x%X, data ptr @ %p\n",
-                    x, y, opcode, s->stream_ptr);
+            av_dlog(s->avctx,
+                    "  block @ (%3d, %3d): encoding 0x%X, data ptr offset %d\n",
+                    x, y, opcode, bytestream2_tell(&s->stream_ptr));
 
             if (!s->is_16bpp) {
                 s->pixel_ptr = s->current_frame.data[0] + x