pgsql: Remove pgrminclude and associated scripts

Remove pgrminclude and associated scripts

Per git log, the last time someone tried to do something with
pgrminclude was around 2011.  And it's always had a tendency of
causing trouble when it was active.  Also, pgcominclude is redundant
with headerscheck.

Discussion: https://www.postgresql.org/message-id/flat/2d4dc7b2-cb2e-49b1-b8ca-ba5f7024f05b%40eisentraut.org

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/5af699066f81547aa75c093544fbd57289d30284

Modified Files
--------------
src/tools/pginclude/README         |  63 --------
src/tools/pginclude/pgcheckdefines | 305 -------------------------------------
src/tools/pginclude/pgcompinclude  |  47 ------
src/tools/pginclude/pgdefine       |  25 ---
src/tools/pginclude/pgfixinclude   |  21 ---
src/tools/pginclude/pgrminclude    | 149 ------------------
6 files changed, 610 deletions(-)