hrtime.h: add note explaining current use of uint64_t [ci skip]
[ruby-core:88678]
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@64554 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
hrtime.h: add note explaining current use of uint64_t [ci skip]
[ruby-core:88678]
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@64554 b2dd03c8-39d4-4d8f-98ff-823fe69b080e