[media] tw5864: remove two unused vars

Remove those two vars that aren't used, as reported by smatch:

drivers/media/pci/tw5864/tw5864-video.c: In function 'tw5864_prepare_frame_headers':
drivers/media/pci/tw5864/tw5864-video.c:1219:16: warning: variable 'space_before_sl_hdr' set but not used [-Wunused-but-set-variable]
  unsigned long space_before_sl_hdr;
                ^~~~~~~~~~~~~~~~~~~
drivers/media/pci/tw5864/tw5864-video.c:1218:6: warning: variable 'sl_hdr' set but not used [-Wunused-but-set-variable]
  u8 *sl_hdr;
      ^~~~~~
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

drivers/media/pci/tw5864/tw5864-video.c

@@ -1215,8 +1215,6 @@ void tw5864_prepare_frame_headers(struct tw5864_input *input)
 	u8 *dst;
 	size_t dst_space;
 	unsigned long flags;
-	u8 *sl_hdr;
-	unsigned long space_before_sl_hdr;
 
 	if (!vb) {
 		spin_lock_irqsave(&input->slock, flags);
@@ -1253,8 +1251,6 @@ void tw5864_prepare_frame_headers(struct tw5864_input *input)
 					      input->width, input->height);
 
 	/* Put slice header */
-	sl_hdr = dst;
-	space_before_sl_hdr = dst_space;
 	tw5864_h264_put_slice_header(&dst, &dst_space, input->h264_idr_pic_id,
 				     input->frame_gop_seqno,
 				     &input->tail_nb_bits, &input->tail);