devicetree: Add bindings for the ATH79 USB phy

devicetree: Add bindings for the ATH79 USB phy

Signed-off-by: Alban Bedel <albeu@free.fr>
Acked-by: Rob Herring <robh@kernel.org>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Ian Campbell <ijc+devicetree@hellion.org.uk>
Cc: Kumar Gala <galak@codeaurora.org>
Cc: Kishon Vijay Abraham I <kishon@ti.com>
Cc: devicetree@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/11496/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>