usb: ohci: Remove unnecessary delays from hc_start and power power-on paths

The usb spec says that we must wait a minimum amount of time after port
power on (exact time is in the hub descriptor), this is something which
we must not only do for root ports but also for external hub ports, which
is why the common usb_hub code already waits a full second after powering
up ports. Having a separate wait for just the root hub in the ohci-hcd
code only leads to doing the waiting twice for the root ports, so drop the
wait from the ohci-hcd code.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>