avcodec/dvdsubdec: Dont mix integers with pointers

Reviewed-by: James Darnley <james.darnley@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/dvdsubdec.c

@@ -213,7 +213,7 @@ static int decode_dvd_subtitles(DVDSubContext *ctx, AVSubtitle *sub_header,
 {
     int cmd_pos, pos, cmd, x1, y1, x2, y2, offset1, offset2, next_cmd_pos;
     int big_offsets, offset_size, is_8bit = 0;
-    const uint8_t *yuv_palette = 0;
+    const uint8_t *yuv_palette = NULL;
     uint8_t *colormap = ctx->colormap, *alpha = ctx->alpha;
     int date;
     int i;
@@ -362,7 +362,7 @@ static int decode_dvd_subtitles(DVDSubContext *ctx, AVSubtitle *sub_header,
                            buf, offset2, buf_size, is_8bit);
                 sub_header->rects[0]->pict.data[1] = av_mallocz(AVPALETTE_SIZE);
                 if (is_8bit) {
-                    if (yuv_palette == 0)
+                    if (!yuv_palette)
                         goto fail;
                     sub_header->rects[0]->nb_colors = 256;
                     yuv_a_to_rgba(yuv_palette, alpha, (uint32_t*)sub_header->rects[0]->pict.data[1], 256);