Merge branch 'net-usbnet-convert-to-new-tasklet-api'

Emil Renner Berthing says:

====================
net: usbnet: convert to new tasklet API

This converts the usbnet driver to use the new tasklet API introduced in
commit 12cc923f1ccc ("tasklet: Introduce new initialization API")

It is split into two commits for ease of reviewing.
====================

Link: https://lore.kernel.org/r/20210123173221.5855-1-esmil@mailme.dk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>