xfs: destroy mutex pag_ici_reclaim_lock before free

The mutex pag_ici_reclaim_lock of xfs_perag_t structure is initialized in
xfs_initialize_perag. If happen errors in xfs_initialize_perag, or free
resources in xfs_free_perag, wo need to destroy the mutex before free
perag.

Signed-off-by: Xiongwei Song <sxwjean@me.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>