dds: Fix palette mode on big endian

Found-By: Michael Niedermayer <michaelni@gmx.at>
Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>

libavcodec/dds.c

@@ -626,8 +626,13 @@ static int dds_decode(AVCodecContext *avctx, void *data,
         int linesize = av_image_get_linesize(avctx->pix_fmt, frame->width, 0);
 
         if (ctx->paletted) {
+            int i;
+            uint32_t *p = (uint32_t *)frame->data[1];
+
             /* Use the first 1024 bytes as palette, then copy the rest. */
-            bytestream2_get_buffer(gbc, frame->data[1], 256 * 4);
+            for (i = 0; i < 256; i++)
+                p[i] = bytestream2_get_le32(gbc);
+
             frame->palette_has_changed = 1;
         }