f2fs: use d_inode(dentry) cleanup dentry->d_inode

[ Upstream commit a6c397a31f58a1d577c2c8d04b624e9baa31951c ]

no logic changes.

Signed-off-by: Zhiguo Niu <zhiguo.niu@unisoc.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>