ext4: don't set i_flags in EXT4_IOC_SETFLAGS

commit b22b1f178f6799278d3178d894f37facb2085765 upstream.

Commit 7990696 uses the ext4_{set,clear}_inode_flags() functions to
change the i_flags automatically but fails to remove the error setting
of i_flags.  So we still have the problem of trashing state flags.
Fix this by removing the assignment.

Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>