xfs: quota: check result of register_shrinker()

[ Upstream commit 3a3882ff26fbdbaf5f7e13f6a0bccfbf7121041d ]

xfs_qm_init_quotainfo() does not check result of register_shrinker()
which was tagged as __must_check recently, reported by sparse.

Signed-off-by: Aliaksei Karaliou <akaraliou.dev@gmail.com>
[darrick: move xfs_qm_destroy_quotainos nearer xfs_qm_init_quotainos]
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>