arm64: renesas: salvator-x: Add board part number to DT bindings

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

Documentation/devicetree/bindings/arm/shmobile.txt

@@ -59,7 +59,7 @@ Boards:
     compatible = "renesas,marzen", "renesas,r8a7779"
   - Porter (M2-LCDP)
     compatible = "renesas,porter", "renesas,r8a7791"
-  - Salvator-X
+  - Salvator-X (RTP0RC7795SIPB0010S)
     compatible = "renesas,salvator-x", "renesas,r8a7795";
   - SILK (RTP0RC7794LCB00011S)
     compatible = "renesas,silk", "renesas,r8a7794"