As a prerequisite for multiple queues, the guest must have MSIX enabled.
Unfortunately, to work around device passthrough bugs, FreeBSD disables
MSIX when running as a VMWare guest due to the hw.pci.honor_msi_blacklist
tunable; this tunable must be disabled for multiple queues.
Also included is various minor changes from the projects/vmxnet branch.
MFC after: 1 month
- Allow the Rx/Tx queue sizes to be configured by tunables
- Bail out earlier if the Tx queue unlikely has enough free
descriptors to hold the frame
- Cleanup some of the offloading capabilities handling