qed: Allow chance for fast ramrod completions

Whenever a ramrod is being sent for some device configuration,
the driver is going to sleep at least 5ms between each iteration
of polling on the completion of the ramrod.

However, in almost every configuration scenario the firmware
would be able to comply and complete the ramrod in a manner of
several usecs. This is especially important in cases where there
might be a lot of sequential configurations applying to the hardware
[e.g., RoCE], in which case the existing scheme might cause some
visible user delays.

This patch changes the completion scheme - instead of immediately
starting to sleep for a 'long' period, allow the device to quickly
poll on the first iteration after a couple of usecs.

Signed-off-by: Yuval Mintz <Yuval.Mintz@caviumnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>