ionic: remove unused variable

Remove a vestigial variable.

Pointed out in https://lore.kernel.org/lkml/20200806143735.GA9232@xsang-OptiPlex-9020/



Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Shannon Nelson <snelson@pensando.io>
Signed-off-by: David S. Miller <davem@davemloft.net>