Revert "f2fs: remove unreachable lazytime mount option parsing"

This reverts commit 54f43a10fa.

The above commit broke the lazytime mount, given

mount("/dev/vdb", "/mnt/test", "f2fs", 0, "lazytime");

CC: stable@vger.kernel.org # 6.11+
Signed-off-by: Daniel Rosenberg <drosen@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Bug: 365027513
Test: mount with lazytime
Link: https://lore.kernel.org/lkml/20241112010820.2788822-1-jaegeuk@kernel.org/T/#u
Change-Id: Ib5b4ddfcec98592f2a84b5cb69d63932bd69b62b

fs/f2fs/super.c

@@ -150,6 +150,8 @@ enum {
 	Opt_mode,
 	Opt_fault_injection,
 	Opt_fault_type,
+	Opt_lazytime,
+	Opt_nolazytime,
 	Opt_quota,
 	Opt_noquota,
 	Opt_usrquota,
@@ -226,6 +228,8 @@ static match_table_t f2fs_tokens = {
 	{Opt_mode, "mode=%s"},
 	{Opt_fault_injection, "fault_injection=%u"},
 	{Opt_fault_type, "fault_type=%u"},
+	{Opt_lazytime, "lazytime"},
+	{Opt_nolazytime, "nolazytime"},
 	{Opt_quota, "quota"},
 	{Opt_noquota, "noquota"},
 	{Opt_usrquota, "usrquota"},
@@ -918,6 +922,12 @@ static int parse_options(struct super_block *sb, char *options, bool is_remount)
 			f2fs_info(sbi, "fault_type options not supported");
 			break;
 #endif
+		case Opt_lazytime:
+			sb->s_flags |= SB_LAZYTIME;
+			break;
+		case Opt_nolazytime:
+			sb->s_flags &= ~SB_LAZYTIME;
+			break;
 #ifdef CONFIG_QUOTA
 		case Opt_quota:
 		case Opt_usrquota: