dt-bindings: usb: add PIC64GX compatibility to mpfs-musb driver

PIC64GX musb is compatible with mpfs-musb, just update compatibility
with fallback

Signed-off-by: Pierre-Henry Moussay <pierre-henry.moussay@microchip.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20240930095449.1813195-3-pierre-henry.moussay@microchip.com


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