arm64: dts: qcom: sm8250: rename spmi node to spmi_bus

The pm8150 dtsi files refer to it as spmi_bus, so change it.

Signed-off-by: Jonathan Marek <jonathan@marek.ca>
Link: https://lore.kernel.org/r/20200523132104.31046-1-jonathan@marek.ca


[bjorn: Dropped qcom, from node name while we're poking at it]
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>