arm64: dts: qcom: sc7280: Add lpass cpu node

Add lpass cpu node for audio on sc7280 based platforms.

Signed-off-by: Srinivasa Rao Mandadapu <quic_srivasam@quicinc.com>
Co-developed-by: Venkata Prasad Potturu <quic_potturu@quicinc.com>
Signed-off-by: Venkata Prasad Potturu <quic_potturu@quicinc.com>
Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/1657200184-29565-9-git-send-email-quic_srivasam@quicinc.com