xfs: cleanup xfs_log_space_wake

Remove the now unused opportunistic parameter, and use the the
xlog_writeq_wake and xlog_reserveq_wake helpers now that we don't have
to care about the opportunistic wakeups.

Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

diff --cc fs/xfs/xfs_log.c
Simple merge

diff --cc fs/xfs/xfs_log.h
Simple merge

diff --cc fs/xfs/xfs_trans_ail.c
Simple merge