In msm8916.dtsi the GPU OPP table is defined under the root node,
whereas in msm8996.dtsi/sdm845.dtsi it is a subnode of the gpu device
(which makes it easier to find).

Move it to the gpu device node to make this consistent.
Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
Link: https://lore.kernel.org/r/20200514112754.148919-2-stephan@gerhold.netSigned-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>