docs: dt: fix references to m_can.txt file

This file was converted to json and renamed. Update its
references accordingly.

Fixes: 824674b5 ("dt-bindings: net: can: Convert M_CAN to json-schema")
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Rob Herring <robh@kernel.org>

Documentation/devicetree/bindings/net/can/tcan4x5x.txt

@@ -14,7 +14,7 @@ Required properties:
                     the interrupt.
 	- interrupts: interrupt specification for data-ready.
 
-See Documentation/devicetree/bindings/net/can/m_can.txt for additional
+See Documentation/devicetree/bindings/net/can/bosch,m_can.yaml for additional
 required property details.
 
 Optional properties:

MAINTAINERS

@@ -10230,7 +10230,7 @@ M:	Dan Murphy <dmurphy@ti.com>
 M:	Sriram Dash <sriram.dash@samsung.com>
 L:	linux-can@vger.kernel.org
 S:	Maintained
-F:	Documentation/devicetree/bindings/net/can/m_can.txt
+F:	Documentation/devicetree/bindings/net/can/bosch,m_can.yaml
 F:	drivers/net/can/m_can/m_can.c
 F:	drivers/net/can/m_can/m_can.h
 F:	drivers/net/can/m_can/m_can_platform.c