* modules/gethrxtime (Depends-on): Add gettime.

* modules/gethrxtime (Depends-on): Add gettime.
* lib/gethrxtime.c: Include "timespec.h" rather than the sys/time / time
business.
(gethrxtime) [! (HAVE_NANOUPTIME
|| (defined CLOCK_MONOTONIC && HAVE_CLOCK_GETTIME)
|| HAVE_MICROUPTIME)]: Fall back on gettime rather than rolling
our own approximation.
* m4/gethrxtime.m4 (gl_PREREQ_GETHRXTIME): Don't require AC_HEADER_TIME
or gettimeofday; no longer needed.