qed: Correct PF-sanity check

Seems like something broke in commit 1408cc1f ("qed: Introduce VFs")
and the function no longer verifies that the vf is indeed a valid one.

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