usb: dwc3: Select 2.0 or 3.0 clk base on maximum_speed

The dwc->maximum_speed is determined through the device capability and
designer's constraint through device tree binding. If none of them
applies, don't let the default coreConsultant setting in GUCTL1 to limit
the device operating speed.

Normally the default setting will not contradict the device capability
or device tree binding. This scenario was found through our internal
tests, not an actual bug in the wild.

Signed-off-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://lore.kernel.org/r/65003b0cc37c08a0d22996009f548247ad18c00c.1713308949.git.Thinh.Nguyen@synopsys.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>