[XFS] Remove unnecessary assertion

Hit this assert because an inode was tagged with XFS_ICI_RECLAIM_TAG but
not XFS_IRECLAIMABLE|XFS_IRECLAIM.  This is because xfs_iget_cache_hit()
first clears XFS_IRECLAIMABLE and then calls __xfs_inode_clear_reclaim_tag()
while only holding the pag_ici_lock in read mode so we can race with
xfs_reclaim_inodes_ag().  Looks like xfs_reclaim_inodes_ag() will do the
right thing anyway so just remove the assert.

Thanks to Christoph for pointing out where the problem was.

Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Reviewed-by: Christoph Hellwig <hch@infradead.org>