avcodec/h264_slice, mpeg4videodec: Don't use %s to write single char

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

libavcodec/h264_slice.c

@@ -2168,9 +2168,9 @@ static int h264_slice_init(H264Context *h, H264SliceContext *sl,
 
     if (h->avctx->debug & FF_DEBUG_PICT_INFO) {
         av_log(h->avctx, AV_LOG_DEBUG,
-               "slice:%d %s mb:%d %c%s%s frame:%d poc:%d/%d ref:%d/%d qp:%d loop:%d:%d:%d weight:%d%s %s\n",
+               "slice:%d %c mb:%d %c%s%s frame:%d poc:%d/%d ref:%d/%d qp:%d loop:%d:%d:%d weight:%d%s %s\n",
                sl->slice_num,
-               (h->picture_structure == PICT_FRAME ? "F" : h->picture_structure == PICT_TOP_FIELD ? "T" : "B"),
+               (h->picture_structure == PICT_FRAME ? 'F' : h->picture_structure == PICT_TOP_FIELD ? 'T' : 'B'),
                sl->mb_y * h->mb_width + sl->mb_x,
                av_get_picture_type_char(sl->slice_type),
                sl->slice_type_fixed ? " fix" : "",

libavcodec/mpeg4videodec.c

@@ -3076,11 +3076,11 @@ static int decode_vop_header(Mpeg4DecContext *ctx, GetBitContext *gb,
 
         if (s->avctx->debug & FF_DEBUG_PICT_INFO) {
             av_log(s->avctx, AV_LOG_DEBUG,
-                   "qp:%d fc:%d,%d %s size:%d pro:%d alt:%d top:%d %spel part:%d resync:%d w:%d a:%d rnd:%d vot:%d%s dc:%d ce:%d/%d/%d time:%"PRId64" tincr:%d\n",
+                   "qp:%d fc:%d,%d %c size:%d pro:%d alt:%d top:%d %cpel part:%d resync:%d w:%d a:%d rnd:%d vot:%d%s dc:%d ce:%d/%d/%d time:%"PRId64" tincr:%d\n",
                    s->qscale, s->f_code, s->b_code,
-                   s->pict_type == AV_PICTURE_TYPE_I ? "I" : (s->pict_type == AV_PICTURE_TYPE_P ? "P" : (s->pict_type == AV_PICTURE_TYPE_B ? "B" : "S")),
+                   s->pict_type == AV_PICTURE_TYPE_I ? 'I' : (s->pict_type == AV_PICTURE_TYPE_P ? 'P' : (s->pict_type == AV_PICTURE_TYPE_B ? 'B' : 'S')),
                    gb->size_in_bits,s->progressive_sequence, s->alternate_scan,
-                   s->top_field_first, s->quarter_sample ? "q" : "h",
+                   s->top_field_first, s->quarter_sample ? 'q' : 'h',
                    s->data_partitioning, ctx->resync_marker,
                    ctx->num_sprite_warping_points, s->sprite_warping_accuracy,
                    1 - s->no_rounding, s->vo_type,