dt-bindings: arm: qcom: Document Huawei Matebook E Go (sc8280xp)

Add compatible for the SC8280XP-based Huawei Matebook E Go,
using its codename, gaokun3, which means it is the 3rd gen gaokun.

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Pengyu Luo <mitltlatltl@gmail.com>
Link: https://lore.kernel.org/r/20241220160530.444864-2-mitltlatltl@gmail.com


Signed-off-by: Bjorn Andersson <andersson@kernel.org>