lavf/oggparsevorbis: Fix change the case of metadata keys issue

The spec in https://xiph.org/vorbis/doc/v-comment.html states that
the metadata keys are case-insensitive, so don't change the case
and update the fate test case.

Fix #7784

Reviewed-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
Signed-off-by: Jun Zhao <barryjzhao@tencent.com>

libavformat/oggparsevorbis.c

@@ -44,7 +44,7 @@ static int ogm_chapter(AVFormatContext *as, uint8_t *key, uint8_t *val)
     int i, cnum, h, m, s, ms, keylen = strlen(key);
     AVChapter *chapter = NULL;
 
-    if (keylen < 9 || sscanf(key, "CHAPTER%03d", &cnum) != 1)
+    if (keylen < 9 || av_strncasecmp(key, "CHAPTER", 7) || sscanf(key+7, "%03d", &cnum) != 1)
         return 0;
 
     if (keylen <= 10) {
@@ -55,7 +55,7 @@ static int ogm_chapter(AVFormatContext *as, uint8_t *key, uint8_t *val)
                            ms + 1000 * (s + 60 * (m + 60 * h)),
                            AV_NOPTS_VALUE, NULL);
         av_free(val);
-    } else if (!strcmp(key + keylen - 4, "NAME")) {
+    } else if (!av_strcasecmp(key + keylen - 4, "NAME")) {
         for (i = 0; i < as->nb_chapters; i++)
             if (as->chapters[i]->id == cnum) {
                 chapter = as->chapters[i];
@@ -91,7 +91,7 @@ int ff_vorbis_comment(AVFormatContext *as, AVDictionary **m,
     const uint8_t *p   = buf;
     const uint8_t *end = buf + size;
     int updates        = 0;
-    unsigned n, j;
+    unsigned n;
     int s;
 
     /* must have vendor_length and user_comment_list_length */
@@ -139,8 +139,7 @@ int ff_vorbis_comment(AVFormatContext *as, AVDictionary **m,
                 return AVERROR(ENOMEM);
             }
 
-            for (j = 0; j < tl; j++)
-                tt[j] = av_toupper(t[j]);
+            memcpy(tt, t, tl);
             tt[tl] = 0;
 
             memcpy(ct, v, vl);

tests/ref/fate/limited_input_seek

@@ -1 +1 @@
-20a1bb9a1cfb23c1fe86f14e6065cd95
+ae878bdaec23f36a63d142165fe57f49

tests/ref/fate/limited_input_seek-copyts

@@ -1 +1 @@
-ec3604b1954ed80de364b8ef491771ce
+ffe8a674bdf38e4f650f91963debc654