Fix obsolete comments in instr_time.h.
Commit
623cc673 removed gettimeofday(), and commits
24c3ce8f and
495ed0ef removed support for very old Windows releases with low accuracy
timers, but references to those things were left behind in comments.
Reported-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/295419.
1659918447%40sss.pgh.pa.us