pgsql: Assume that we have utime() and .

Assume that we have utime() and <utime.h>.

These are required by POSIX since SUSv2, and no live platforms fail
to provide them.  On Windows, utime() exists and we bring our own
<utime.h>, so we're good there too.  So remove the configure probes
and ad-hoc substitute code.  We don't need to check for utimes()
anymore either, since that was only used as a substitute.

In passing, make the Windows build include <sys/utime.h> only where
we need it, not everywhere.

This is part of a series of commits to get rid of no-longer-relevant
configure checks and dead src/port/ code.  I'm committing them separately
to make it easier to back out individual changes if they prove less
portable than I expect.

Discussion: https://postgr.es/m/15379.1582221614@sss.pgh.pa.us

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/481c8e9232386e289fbd3e8f75893ae8d9814298

Modified Files
--------------
configure                           |  4 ++--
configure.in                        |  3 ---
src/backend/libpq/pqcomm.c          | 18 ++----------------
src/backend/utils/init/miscinit.c   | 27 ++-------------------------
src/include/pg_config.h.in          |  9 ---------
src/include/port/win32_msvc/utime.h |  2 ++
src/include/port/win32_port.h       |  1 -
src/tools/msvc/Solution.pm          |  3 ---
8 files changed, 8 insertions(+), 59 deletions(-)