dt-bindings: clock: qcom: Document the X1E80100 GPU Clock Controller

Add bindings documentation for the X1E80100 Graphics Clock Controller.

Signed-off-by: Rajendra Nayak <quic_rjendra@quicinc.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Abel Vesa <abel.vesa@linaro.org>
Link: https://lore.kernel.org/r/20240202-x1e80100-clock-controllers-v4-3-7fb08c861c7c@linaro.org
Signed-off-by: Bjorn Andersson <andersson@kernel.org>