f2fs: spread f2fs_set_inode_flags()

This patch changes codes as below:
- use f2fs_set_inode_flags() to update i_flags atomically to avoid
potential race.
- synchronize F2FS_I(inode)->i_flags to inode->i_flags in
f2fs_new_inode().
- use f2fs_set_inode_flags() to simply codes in f2fs_quota_{on,off}.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

fs/f2fs/namei.c

@@ -122,6 +122,8 @@ static struct inode *f2fs_new_inode(struct inode *dir, umode_t mode)
 	if (F2FS_I(inode)->i_flags & F2FS_PROJINHERIT_FL)
 		set_inode_flag(inode, FI_PROJ_INHERIT);
 
+	f2fs_set_inode_flags(inode);
+
 	trace_f2fs_new_inode(inode, 0);
 	return inode;