dt-bindings: i2c: bcm2835: Add brcm,bcm2711 compatible

Add a new compatible for the BCM2711, which hasn't the clock stretch bug.
Signed-off-by: NStefan Wahren <wahrenst@gmx.net>
Reviewed-by: NEric Anholt <eric@anholt.net>
Reviewed-by: NRob Herring <robh@kernel.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Documentation/devicetree/bindings/i2c/brcm,bcm2835-i2c.txt

 Broadcom BCM2835 I2C controller
 
 Required properties:
-- compatible : Should be "brcm,bcm2835-i2c".
+- compatible : Should be one of:
+	"brcm,bcm2711-i2c"
+	"brcm,bcm2835-i2c"
 - reg: Should contain register location and length.
 - interrupts: Should contain interrupt.
 - clocks : The clock feeding the I2C controller.