bhyve: scan PCI device ID to properly set BDSM address

The address and size of the BDSM register has changed in recent Intel GPUs. To
account for that change, we have to detect the GPU generation. We've recently
added all known PCI IDs of Intel GPUs from Linux. Make use of this header to
scan the device ID and properly set the BDSM address.

Note that even though a bunch of devices is listed in our device array, not all
device will work properly. Especially some old devices may not support VT-d,
required for passthrough in general, at all.

Reviewed by: jhb
MFC after: 1 week
Sponsored by: Beckhoff Automation GmbH & Co. KG
Differential Revision: https://reviews.freebsd.org/D50807