arm64: dts: qcom: sc8280xp: Fix PMU interrupt

arm64: dts: qcom: sc8280xp: Fix PMU interrupt

PPI interrupt should be 7 for the PMU.

Cc: Johan Hovold <johan+linaro@kernel.org>
Fixes: 199bdb9eaef1 ("arm64: dts: qcom: add SC8280XP platform")
Reported-by: Steve Capper <Steve.Capper@arm.com>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Andrew Halaney <ahalaney@redhat.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220713143429.22624-1-manivannan.sadhasivam@linaro.org