The OMAP OHCI and EHCI USB host bindings follow the generic binding, so
add the compatibles and remove the old txt binding docs.

The examples in omap-usb-host.txt don't match actual users, so update
them dropping the fallback compatible.
Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20230110-dt-usb-v3-3-5af0541fcf8c@kernel.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>