f2fs: prevent atomic file from being dirtied before commit

[ Upstream commit fccaa81d ]

Keep atomic file clean while updating and make it dirtied during commit
in order to avoid unnecessary and excessive inode updates in the previous
fix.

Fixes: 4bf78322 ("f2fs: mark inode dirty for FI_ATOMIC_COMMITTED flag")
Signed-off-by: Daeho Jeong <daehojeong@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>