arm64: dts: qcom: sc7280-crd: add Bluetooth VDDIO supply

Bluetooth requires VDDIO supply and Doug Anderson suggested it is
vreg_l18b_1p8.  Add one to satisfy `dtbs_check`:

  sc7280-crd-r3.dtb: bluetooth: 'vddio-supply' is a required property

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20230816060502.16789-1-krzysztof.kozlowski@linaro.org


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