One final pass in opte-drv (#214)

- Did a final sweep in opte-drv to see if there was anything else to
  migrate over to xde.

- Moved over the _Unwind_Resume hack. It seems xde has been working
  fine without it, but I also notice the Rust issue that originally
  prompted me to create this hack is still marked as open. So I
  thought it would be best to migrate the hack over to xde just as a
  safeguard against the problem coming back until that Rust issue is
  resolved.

  rust-lang/rust#47493

README.adoc

@@ -28,11 +28,6 @@ uses the opte crate to implement the Oxide VPC network.
 
 opte-ioctl:: The userland library used for interacting with OPTE.
 
-opte-drv (obsolete):: A kernel module which hooks into the network
-path between viona (bhyve) and mac, feeding all packets into opte-core
-for processing. This module has been rendered obsolete by `xde`, but
-it still remains until all features are transitioned over.
-
 opteadm:: The command line utility used to configure and inspect OPTE.
 This is meant to be used by an operator, not by a client program.