dt-bindings: can: mcp251x: add mcp25625 support

Fully compatible with mcp2515, the mcp25625 have integrated transceiver.

This patch add the mcp25625 to the device tree bindings documentation.
Signed-off-by: Sean Nyekjaer <sean@geanix.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

Documentation/devicetree/bindings/net/can/microchip,mcp251x.txt

@@ -4,6 +4,7 @@ Required properties:
  - compatible: Should be one of the following:
    - "microchip,mcp2510" for MCP2510.
    - "microchip,mcp2515" for MCP2515.
+   - "microchip,mcp25625" for MCP25625.
  - reg: SPI chip select.
  - clocks: The clock feeding the CAN controller.
  - interrupts: Should contain IRQ line for the CAN controller.