Doc: modernize documentation for lo_create()/lo_creat().
At this point lo_creat() is a legacy function with little if any
real use-case, so describing it first doesn't make much sense.
Describe lo_create() first, and then explain lo_creat() as a
backwards-compatibility alternative.
Discussion: https://postgr.es/m/
164353261519.713.
8748040527537500758@wrigleys.postgresql.org