arm64: dts: qcom: Use gcc clock enums

Now that header defining gcc clocks is upstream, use the enums instead
of numbers

Signed-off-by: Vinod Koul <vkoul@kernel.org>
Link: https://lore.kernel.org/r/20191106084604.1746544-1-vkoul@kernel.org


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