ext4: remove the redundant folio_wait_stable()

__filemap_get_folio() with FGP_WRITEBEGIN parameter has already wait
for stable folio, so remove the redundant folio_wait_stable() in
ext4_da_write_begin(), it was left over from the commit cc883236
("ext4: drop unnecessary journal handle in delalloc write") that
removed the retry getting page logic.

Fixes: cc883236 ("ext4: drop unnecessary journal handle in delalloc write")
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20240419023005.2719050-1-yi.zhang@huaweicloud.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

fs/ext4/inode.c

@@ -2887,9 +2887,6 @@ static int ext4_da_write_begin(struct file *file, struct address_space *mapping,
 	if (IS_ERR(folio))
 		return PTR_ERR(folio);
 
-	/* In case writeback began while the folio was unlocked */
-	folio_wait_stable(folio);
-
 #ifdef CONFIG_FS_ENCRYPTION
 	ret = ext4_block_write_begin(folio, pos, len, ext4_da_get_block_prep);
 #else