ext4: indicate that fast_commit is available via /sys/fs/ext4/feature/...

Signed-off-by: Theodore Ts'o <tytso@mit.edu>

fs/ext4/sysfs.c

@@ -315,6 +315,7 @@ EXT4_ATTR_FEATURE(casefold);
 EXT4_ATTR_FEATURE(verity);
 #endif
 EXT4_ATTR_FEATURE(metadata_csum_seed);
+EXT4_ATTR_FEATURE(fast_commit);
 
 static struct attribute *ext4_feat_attrs[] = {
 	ATTR_LIST(lazy_itable_init),
@@ -331,6 +332,7 @@ static struct attribute *ext4_feat_attrs[] = {
 	ATTR_LIST(verity),
 #endif
 	ATTR_LIST(metadata_csum_seed),
+	ATTR_LIST(fast_commit),
 	NULL,
 };
 ATTRIBUTE_GROUPS(ext4_feat);