drm/hyperv: Remove support for Hyper-V 2008 and 2008R2/Win7

drm/hyperv: Remove support for Hyper-V 2008 and 2008R2/Win7

The DRM Hyper-V driver has special case code for running on the first
released versions of Hyper-V: 2008 and 2008 R2/Windows 7.  These versions
are now out of support (except for extended security updates) and lack
support for performance features that are needed for effective production
usage of Linux guests.

The negotiation of the VMbus protocol versions required by these old
Hyper-V versions has been removed from the VMbus driver.  So now remove
the handling of these VMbus protocol versions from the DRM Hyper-V
driver.

Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Reviewed-by: Deepak Rawat <drawat.floss@gmail.com>
Reviewed-by: Andrea Parri (Microsoft) <parri.andrea@gmail.com>
Link: https://lore.kernel.org/r/1651509391-2058-5-git-send-email-mikelley@microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>