tg3: Remove incorrect switch to aux power

During probe, the driver is incorrectly switching the power to Vaux on
the 5717 and later devices. At this point, we are in D0 state and
drawing maximum power. We also definitely have Vmain available. It
doesn't make sense to switch to Vaux since it has a lesser maximum power
draw and we might go over the limit. On a new system, we observe that
not all ports are recognized in some of the slots with this call in
place.

Signed-off-by: Nithin Nayak Sujir <nsujir@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>