disable CLOCK_*_CPUTIME_ID and CPERF_CLOCK on Windows
disable CLOCK_*_CPUTIME_ID and CPERF_CLOCK on Windows

They're emulated by Cygwin and MinGW, and don't provide any particularly
interesting data.

Signed-off-by: Steven Noonan <4068f0880b399410602d694b3cc711c8a8f4727e@uplinklabs.net>

tycho/clockperf,tycho/clockperf