tg3: Fix 57765 A0 bootcode race condition

On A0 revision of 57765 asic rev devices, the bootcode will perform some
hardware operations, after the magic signature is presented, that will
collide with setup operations performed by the driver.  The best way to
avoid the contention is to have the driver delay an additional 10
milliseconds.  B0 revisions of the chip will make this workaround
unnecessary.

Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Signed-off-by: Benjamin Li <benli@broadcom.com>
Reviewed-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>