ionic: report users coalesce request

The user's request for an interrupt coalescing value gets
translated into a hardware value to be used with the NIC,
and was getting reported back based on the hw value, which,
due to hw tic resolution, could be reported as a different
number than what the user originally asked for.  This code
now tracks both the user request and what was put into the
hardware so we can report back to the user what they
requested.

Signed-off-by: Shannon Nelson <snelson@pensando.io>
Signed-off-by: David S. Miller <davem@davemloft.net>