dt-bindings: arm: ti: Add bindings for AM625 SoC

The AM62 SoC family is the follow on AM335x built on K3 Multicore SoC
architecture platform, providing ultra-low-power modes, dual display,
multi-sensor edge compute, security and other BOM-saving integration.
The AM62 SoC targets broad market to enable applications such as
Industrial HMI, PLC/CNC/Robot control, Medical Equipment, Building
Automation, Appliances and more.

Some highlights of this SoC are:

* Quad-Cortex-A53s (running up to 1.4GHz) in a single cluster.
  Pin-to-pin compatible options for single and quad core are available.
* Cortex-M4F for general-purpose or safety usage.
* Dual display support, providing 24-bit RBG parallel interface and
  OLDI/LVDS-4 Lane x2, up to 200MHz pixel clock support for 2K display
  resolution.
* Selectable GPUsupport, up to 8GFLOPS, providing better user experience
  in 3D graphic display case and Android.
* PRU(Programmable Realtime Unit) support for customized programmable
  interfaces/IOs.
* Integrated Giga-bit Ethernet switch supporting up to a total of two
  external ports (TSN capable).
* 9xUARTs, 5xSPI, 6xI2C, 2xUSB2, 3xCAN-FD, 3x eMMC and SD, GPMC for
  NAND/FPGA connection, OSPI memory controller, 3xMcASP for audio,
  1x CSI-RX-4L for Camera, eCAP/eQEP, ePWM, among other peripherals.
* Dedicated Centralized System Controller for Security, Power, and
  Resource Management.
* Multiple low power modes support, ex: Deep sleep,Standby, MCU-only,
  enabling battery powered system design.

AM625 is the first device of the family. Add DT bindings for the same.

More details can be found in the Technical Reference Manual:
https://www.ti.com/lit/pdf/spruiv7Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Acked-by: Rob Herring <robh@kernel.org>
Reviewed-by: Bryan Brattlof <bb@ti.com>
Link: https://lore.kernel.org/r/20220225120239.1303821-3-vigneshr@ti.com

Documentation/devicetree/bindings/arm/ti/k3.yaml

@@ -46,6 +46,12 @@ properties:
                   - ti,j7200-evm
               - const: ti,j7200
 
+      - description: K3 AM625 SoC
+        items:
+          - enum:
+              - ti,am625-sk
+          - const: ti,am625
+
       - description: K3 AM642 SoC
         items:
           - enum: