dt-binding: pcf85063: Add an entry for pca85073a

The PCA85073A RTC has the same programming model as the PCF85063A.

Add a compatible entry for it.
Signed-off-by: Fabio Estevam <festevam@denx.de>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20220419014445.341444-1-festevam@gmail.com

Documentation/devicetree/bindings/rtc/nxp,pcf85063.txt

@@ -2,6 +2,7 @@
 
 Required properties:
 - compatible: Should one of contain:
+	"nxp,pca85073a",
 	"nxp,pcf85063",
 	"nxp,pcf85063a",
 	"nxp,pcf85063tp",