ice: sleep, don't busy-wait, in the SQ send retry loop

commit b488ae52

 upstream.

10 ms is a lot of time to spend busy-waiting. Sleeping is clearly
allowed here, because we have just returned from ice_sq_send_cmd(),
which takes a mutex.

On kernels with HZ=100, this msleep may be twice as long, but I don't
think it matters.
I did not actually observe any retries happening here.

Signed-off-by: Michal Schmidt <mschmidt@redhat.com>
Reviewed-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Tested-by: Sunitha Mekala <sunithax.d.mekala@intel.com> (A Contingent worker at Intel)
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Signed-off-by: Liwei Song <liwei.song@windriver.com>