drm/vmwgfx: Implement MSI/MSI-X support for IRQs

SVGAv3 deprecates legacy interrupts and adds support for MSI/MSI-X. With
MSI the driver visible side remains largely unchanged but with MSI-X
each interrupt gets delivered on its own vector.

Add support for MSI/MSI-X while preserving the old functionality for
SVGAv2. Code between the SVGAv2 and SVGAv3 is exactly the same, only
the number of available vectors changes, in particular between legacy
and MSI-X interrupts.

Signed-off-by: Zack Rusin <zackr@vmware.com>
Reviewed-by: Martin Krastev <krastevm@vmware.com>
Reviewed-by: Maaz Mombasawala <mombasawalam@vmware.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220307162412.1183049-1-zack@kde.org