dt-bindings: usb: Remove obsolete brcm,bcm3384-usb.txt

The "brcm,bcm3384-ohci" and "brcm,bcm3384-ehci" compatibles are already
documented in generic-ohci.yaml and generic-ehci.yaml, respectively, so
remove the old txt binding.

Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20230110-dt-usb-v3-1-5af0541fcf8c@kernel.org


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