BCM2711-based Raspberry Pi boards (4B, CM4 and 400) multiplex the I2C0
controller over two sets of pins, GPIO0+1 and GPIO44+45. The former is
exposed on the 40-pin header, while the latter is used for the CSI and
DSI connectors.

Add a pinctrl-based I2C bus multiplexer to bcm2711-rpi.dtsi to model
this multiplexing. The two child buses are named i2c0_0 and i2c0_1.

Note that if you modified the dts before to add devices to the i2c bus
appearing on pins gpio0 + gpio1 (either directly in the dts or using an
overlay), you have to put these into the i2c0_0 node introduced here
now.
Signed-off-by: Uwe Kleine-König <uwe@kleine-koenig.org>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Link: https://lore.kernel.org/r/20240402000424.4650-8-laurent.pinchart@ideasonboard.comSigned-off-by: Florian Fainelli <florian.fainelli@broadcom.com>