dt-bindings: remoteproc: qcom: adsp: Add SDM660 ADSP

Add a compatible string for SDM660 ADSP.

Signed-off-by: Konrad Dybcio <konrad.dybcio@somainline.org>
Link: https://lore.kernel.org/r/20210728215212.18217-1-konrad.dybcio@somainline.org


[bjorn: Use the -pas suffix]
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>