MB-7629 Add option to skip sorting in native btree updater

For compactor delta logs update, we do not want to
sort the log files since they are already sorted.

Change-Id: I298db564db2ebba677f0aa58924d97461348a0d5
Reviewed-on: http://review.couchbase.org/32315
Reviewed-by: Volker Mische <volker.mische@gmail.com>
Reviewed-by: Filipe David Borba Manana <fdmanana@gmail.com>
Tested-by: Filipe David Borba Manana <fdmanana@gmail.com>