Change lookup of OS name on JVM backend
Change lookup of OS name on JVM backend

nqp::jvmgetproperties is where we have that information on JVM. We use
the same differentiation in src/core/VM.pm.

Unbusts the JVM build.

tbrowder/rakudo,softmoth/rakudo,labster/rakudo,Gnouc/rakudo,nbrown/rakudo,labster/rakudo,tony-o/rakudo,Gnouc/rakudo,rakudo/rakudo,MasterDuke17/rakudo,labster/rakudo,tony-o/rakudo,nbrown/rakudo,rakudo/rakudo,tony-o/rakudo,tbrowder/rakudo,tony-o/rakudo,lucasbuchala/rakudo,nbrown/rakudo,MasterDuke17/rakudo,softmoth/rakudo,MasterDuke17/rakudo,salortiz/rakudo,lucasbuchala/rakudo,lucasbuchala/rakudo,tbrowder/rakudo,nbrown/rakudo,Gnouc/rakudo,awwaiid/rakudo,labster/rakudo,softmoth/rakudo,rakudo/rakudo,nbrown/rakudo,salortiz/rakudo,Gnouc/rakudo,salortiz/rakudo,tony-o/rakudo,awwaiid/rakudo,salortiz/rakudo,labster/rakudo,tbrowder/rakudo,tbrowder/rakudo,tbrowder/rakudo,lucasbuchala/rakudo,awwaiid/rakudo,rakudo/rakudo,MasterDuke17/rakudo,Gnouc/rakudo,salortiz/rakudo,salortiz/rakudo,lucasbuchala/rakudo,nbrown/rakudo,labster/rakudo,MasterDuke17/rakudo,Gnouc/rakudo,rakudo/rakudo,softmoth/rakudo,awwaiid/rakudo,MasterDuke17/rakudo,awwaiid/rakudo,softmoth/rakudo,rakudo/rakudo,tony-o/rakudo