dt-bindings: display/msm/gpu: define reg-names in top-level

All devices should (and actually do) have same order of entries, if
possible.  That's the case for reg/reg-names, so define the reg-names in
top-level to enforce that.

Acked-by: Conor Dooley <[email protected]>
Signed-off-by: Krzysztof Kozlowski <[email protected]>
Patchwork: https://patchwork.freedesktop.org/patch/600510/
Link: https://lore.kernel.org/r/20240623-qcom-adreno-dts-bindings-driver-v2-2-9496410de992@linaro.org
Signed-off-by: Dmitry Baryshkov <[email protected]>

Author: krzk

Documentation/devicetree/bindings/display/msm/gpu.yaml

@@ -46,7 +46,10 @@ properties:
 
   reg-names:
     minItems: 1
-    maxItems: 3
+    items:
+      - const: kgsl_3d0_reg_memory
+      - const: cx_mem
+      - const: cx_dbgc
 
   interrupts:
     maxItems: 1