• Explicitly call twe_done() to poll the hardware when looping in twe_start() to simulate the behavior on 4.x where the driver dropped spl to allow interrupts to run to free up space in the command queue. Be careful to only poll if we are going to make at least one more attempt to queue the current command. Also, when polling, be careful to not call twe_startio() to queue more commands to avoid recursion.
• Move the buffer for formatting AEN messages into the softc instead of using a single driver-wide static buffer.

Requested by: scottl (1)
Tested by: Mike Tancsa @ Sentex