ena: Move reset completion logging to the reset function

While ena_restore_device is called from the reset task, it can also be
called from other locations in the driver, for example in netmap
specific code. Move the reset completion logging to reset task, so it
better represents when the reset actually happened.

Obtained from: Semihalf
MFC after: 2 weeks
Sponsored by: Amazon, Inc.

(cherry picked from commit d209ffee155dd5e505f174a356c8f50c96ebf57e)