dt-bindings: media: cal: update binding to add PHY LDO errata support

Update Device Tree bindings for the CAL driver to add support for
the CSI2 PHY LDO errata workaround for pre-es2 devices.

Signed-off-by: Benoit Parrot <bparrot@ti.com>
Signed-off-by: Jyri Sarha <jsarha@ti.com>

Documentation/devicetree/bindings/media/ti-cal.txt

@@ -7,7 +7,9 @@ processing capability to connect CSI2 image-sensor modules to the
 DRA72x device.
 
 Required properties:
-- compatible: must be "ti,dra72-cal"
+- compatible:
+ Should be "ti,dra72-cal", for DRA72 controllers
+ Should be "ti,dra72-pre-es2-cal", for DRA72 controllers pre ES2.0
 - reg:	CAL Top level, Receiver Core #0, Receiver Core #1 and Camera RX
 	control address space
 - reg-names: cal_top, cal_rx_core0, cal_rx_core1, and camerrx_control