pgsql: Refactor DLSUFFIX handling

Refactor DLSUFFIX handling

Move DLSUFFIX from makefiles into header files for all platforms.
Move the DLSUFFIX assignment from src/makefiles/ to src/templates/,
have configure read it, and then substitute it into Makefile.global
and pg_config.h. This avoids the need for all makefile rules that
need it to locally set CPPFLAGS. It also resolves an inconsistent
setup between the two Windows build systems.

Reviewed-by: Andres Freund <andres(at)anarazel(dot)de>
Discussion: https://www.postgresql.org/message-id/2f9861fb-8969-9005-7518-b8e60f2bead9@enterprisedb.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/23119d51a14c046dae35ae5e6ad9e35982d044fd

Modified Files
--------------
config/python.m4 | 4 +++-
configure | 14 +++++++++++++-
configure.ac | 7 +++++++
src/Makefile.global.in | 2 ++
src/backend/jit/Makefile | 2 --
src/backend/utils/fmgr/Makefile | 2 --
src/backend/utils/fmgr/dfmgr.c | 5 -----
src/bin/pg_upgrade/Makefile | 2 +-
src/include/pg_config.h.in | 3 +++
src/include/port/win32_port.h | 3 ---
src/interfaces/ecpg/test/Makefile | 1 -
src/makefiles/Makefile.aix | 1 -
src/makefiles/Makefile.cygwin | 1 -
src/makefiles/Makefile.darwin | 2 --
src/makefiles/Makefile.freebsd | 2 --
src/makefiles/Makefile.hpux | 6 ------
src/makefiles/Makefile.linux | 2 --
src/makefiles/Makefile.netbsd | 2 --
src/makefiles/Makefile.openbsd | 2 --
src/makefiles/Makefile.solaris | 2 --
src/makefiles/Makefile.win32 | 1 -
src/template/cygwin | 2 ++
src/template/hpux | 7 +++++++
src/template/win32 | 2 ++
src/test/regress/GNUmakefile | 3 +--
src/tools/msvc/Solution.pm | 1 +
26 files changed, 42 insertions(+), 39 deletions(-)