xfs: move and rename xfs_trans_committed_bulk

Ever since the CIL and delayed logging was introduced,
xfs_trans_committed_bulk() has been a purely CIL checkpoint
completion function and not a transaction commit completion
function. Now that we are adding log specific updates to this
function, it really does not have anything to do with the
transaction subsystem - it is really log and log item level
functionality.

This should be part of the CIL code as it is the callback
that moves log items from the CIL checkpoint to the AIL. Move it
and rename it to xlog_cil_ail_insert().

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>