dt-bindings: arm: stm32: Add Engicam i.Core STM32MP1 EDIMM2.2 Starter Kit

i.Core STM32MP1 is an EDIMM SoM based on STM32MP157A from Engicam.

EDIMM2.2 Starter Kit is an EDIMM 2.2 Form Factor Capacitive Evaluation
Board from Engicam.

i.Core STM32MP1 needs to mount on top of this Evaluation board for
creating complete i.Core STM32MP1 EDIMM2.2 Starter Kit.

Add bindings for it.
Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Alexandre Torgue <alexandre.torgue@foss.st.com>

Documentation/devicetree/bindings/arm/stm32/stm32.yaml

@@ -67,7 +67,9 @@ properties:
 
       - description: Engicam i.Core STM32MP1 SoM based Boards
         items:
-          - const: engicam,icore-stm32mp1-ctouch2    # STM32MP1 Engicam i.Core STM32MP1 C.TOUCH 2.0
+          - enum:
+              - engicam,icore-stm32mp1-ctouch2       # STM32MP1 Engicam i.Core STM32MP1 C.TOUCH 2.0
+              - engicam,icore-stm32mp1-edimm2.2      # STM32MP1 Engicam i.Core STM32MP1 EDIMM2.2 Starter Kit
           - const: engicam,icore-stm32mp1            # STM32MP1 Engicam i.Core STM32MP1 SoM
           - const: st,stm32mp157