net: ipa: ignore the microcontroller log event

The IPA-resident microcontroller has the ability to log various
activity in an area of IPA shared memory.  When the microcontroller
starts it generates an event to the AP to provide information about
the log.

We don't support reading this log, and we can safely ignore the
event.  So do that rather than treating the log info event we
receive as "unsupported."

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>