Removed a compiler warning about the quality of RDTSC
Removed a compiler warning about the quality of RDTSC

- replaced it by a simple comment, since it also holds for most of the other time sources, this is a general problem that needs to be solved case by case

smarr/OmniVM,smarr/OmniVM,smarr/OmniVM,smarr/OmniVM,smarr/OmniVM,smarr/OmniVM,smarr/OmniVM,smarr/OmniVM