report: split up osVersion and machine values

Prior to this commit, on non-Windows platforms, the "osVersion"
value was prepended to the "machine" value.

PR-URL: https://github.com/nodejs/node/pull/25755


Reviewed-By: Gireesh Punathil <gpunathi@in.ibm.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Richard Lau <riclau@uk.ibm.com>