[COMMITTERS] pgsql: Refactor the way code is shared between some range type function

Refactor the way code is shared between some range type functions. Functions like range_eq, range_before etc. are exposed at the SQL-level, but they're also used internally by the GiST consistent support function. The code sharing was done by a hack, TrickFunctionCall2, which relied on the knowled

[COMMITTERS] pgsql: Refactor the way code is shared between some range type function

Refactor the way code is shared between some range type functions. Functions like range_eq, range_before etc. are exposed at the SQL-level, but they're also used internally by the GiST consistent support function. The code sharing was done by a hack, TrickFunctionCall2, which relied on the knowled