ARM: dts: qcom: apq8060-dragonboard: move regulators out of simple-bus

Regulators is not a bus, so drop incomplete simple-bus usage to fix dtbs
W=1 warnings:

  Warning (simple_bus_reg): /regulators/regulator-fixed: missing or empty reg/ranges property
  Warning (simple_bus_reg): /regulators/xc622a331mrg: missing or empty reg/ranges property
  Warning (simple_bus_reg): /regulators/nds332p: missing or empty reg/ranges property
  Warning (simple_bus_reg): /regulators/txb0104rgyr: missing or empty reg/ranges property

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20230420075053.41976-8-krzysztof.kozlowski@linaro.org