qede: Fix forcing high speeds

While '0xdead' and '0xbeef' are "great" values, we should
use the correct SPEED_* values instead.

Fixes: 054c67d1

 ("qed*: Add support for ethtool link_ksettings callbacks")
Signed-off-by: Yuval Mintz <Yuval.Mintz@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>