octeon_ep: initialise control mbox tasks before using APIs

Initialise various workqueue tasks and queue interrupt poll task
before the first invocation of any control net APIs. Since
octep_ctrl_net_get_info was called before the control net receive
work task was initialised or even the interrupt poll task was
queued, the function call wasn't returning actual firmware
info queried from Octeon.

Fixes: 8d6198a1

 ("octeon_ep: support to fetch firmware info")
Signed-off-by: Shinas Rasheed <srasheed@marvell.com>
Reviewed-by: Michal Schmidt <mschmidt@redhat.com>
Link: https://lore.kernel.org/r/20231206135228.2591659-1-srasheed@marvell.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>