guestagent: add support for Windows 2019
guestagent: add support for Windows 2019

Server editions stopped bumping the major/minor versions and Windows
2019 is also 10.0 (just like Windows 2016). To distinguish the versions
we have to match build numbers.

Final build number of Windows Server 2016 is 14939 and everything from
0 to 14939 (including) is Windows Server 2016. Final build number of
Windows Server 2019 is 17764, so any version with build number above
14939 up to 17764 is Windows Server 2019.

Reference:
https://techcommunity.microsoft.com/t5/Windows-Server-Insiders/Windows-Server-2019-version-info/m-p/293112/highlight/true#M859

Change-Id: Iffacc52891afa37fe4f1a7ca1f31652cebc07cb7
Bug-Url: https://bugzilla.redhat.com/1656346
Signed-off-by: Tomáš Golembiovský <195f5d66b6993ab87f99c3e490190d04420e3560@redhat.com>

oVirt/ovirt-guest-agent,oVirt/ovirt-guest-agent,oVirt/ovirt-guest-agent,oVirt/ovirt-guest-agent