pgsql: Remove support for old realpath() API

Remove support for old realpath() API

The now preferred way to call realpath() is by passing NULL as the
second argument and get a malloc'ed result.  We still supported the
old way of providing our own buffer as a second argument, for some
platforms that didn't support the new way yet.  Those were only
Solaris less than version 11 and some older AIX versions (7.1 and
newer appear to support the new variant).  We don't support those
platforms versions anymore, so we can remove this extra code.

Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Discussion: https://www.postgresql.org/message-id/flat/9e638b49-5c3f-470f-a392-2cbedb2f7855%40eisentraut.org

Branch
------
master

Details
-------
https://git.postgresql.org/pg/commitdiff/94980c45674fc2d1125f3ba7ce0bb5d34f770e00

Modified Files
--------------
src/common/exec.c | 19 -------------------
1 file changed, 19 deletions(-)