xfs: move recovery needed state updates to xfs_log_mount_finish

xfs_log_mount_finish() needs to know if recovery is needed or not to
make decisions on whether to flush the log and AIL.  Move the
handling of the NEED_RECOVERY state out to this function rather than
needing a temporary variable to store this state over the call to
xlog_recover_finish().

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: Darrick J. Wong <djwong@kernel.org>