pgsql: Remove RangeIOData->typiofunc

Remove RangeIOData->typiofunc

We used to carry the I/O function OID in RangeIOData, but it's not used
for anything. Since the struct is not exposed to the world anyway, we
can simplify it a bit. Also, rename the FmgrInfo member to match
the accompanying 'typioparam' and put them in a more sensible order.

Reviewed by Tom Lane and Paul Jungwirth.

Discussion: https://postgr.es/m/20200304215711.GA8732@alvherre.pgsql

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/a77315fdf2a197a925e670be2d8b376c4ac02efc

Modified Files
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src/backend/utils/adt/rangetypes.c | 26 +++++++++++++-------------
1 file changed, 13 insertions(+), 13 deletions(-)