be2net: increment work_counter in be_worker

The commit 609ff3bb ("be2net: add code to display temperature of ASIC")
adds support to display temperature of ASIC but there is missing
increment of work_counter in be_worker. Because of this 1) the
function be_cmd_get_die_temperature is called every 1 second instead
of every 32 seconds 2) be_cmd_get_die_temperature is called, although
it is not supported.  This patch fixes this bug.

Signed-off-by: Ivan Vecera <ivecera@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>