[PATCH v2] dt-bindings: media: i2c: dongwoon,dw9768: add Giantec GT9764

[Mingxuan Guo <gmx472@qq.com>]

The GT9764 is one of Giantec's VCM driver parts and shares the register
model of the GT9769 already covered by this binding: the vendor's VCM
driver application note (AN971) covers GT9764, GT9767, GT9768, GT9769,
GT9772 and GT9778, all built around the same 10-bit DAC with the AAC
actuator-control extensions.

Document it as a specific compatible that requires the GT9769 as its
fallback, so the existing driver binds through the GT9769 entry and no
driver change is needed.

Signed-off-by: Mingxuan Guo <gmx472@qq.com>
---
Changes in v2:
- Use the GT9769 as a fallback compatible instead of a standalone driver
  entry (Conor Dooley), and drop the driver patch accordingly; this also
  clears the Media CI warning about the compatible being undocumented.

 Documentation/devicetree/bindings/media/i2c/dongwoon,dw9768.yaml | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/media/i2c/dongwoon,dw9768.yaml b/Documentation/devicetree/bindings/media/i2c/dongwoon,dw9768.yaml
--- a/Documentation/devicetree/bindings/media/i2c/dongwoon,dw9768.yaml
+++ b/Documentation/devicetree/bindings/media/i2c/dongwoon,dw9768.yaml
@@ -20,9 +20,13 @@ description: |-
 
 properties:
   compatible:
-    enum:
-      - dongwoon,dw9768 # for DW9768 VCM
-      - giantec,gt9769  # for GT9769 VCM
+    oneOf:
+      - enum:
+          - dongwoon,dw9768 # for DW9768 VCM
+          - giantec,gt9769  # for GT9769 VCM
+      - items:
+          - const: giantec,gt9764 # for GT9764 VCM
+          - const: giantec,gt9769 # fallback, same register model
 
   reg:
     maxItems: 1