Add a simple rpmsg support for mt8183 SCP, that use IPI / IPC directly.
Signed-off-by: NPi-Hsun Shih <pihsun@chromium.org>
Link: https://lore.kernel.org/r/20191112110330.179649-4-pihsun@chromium.orgSigned-off-by: NBjorn Andersson <bjorn.andersson@linaro.org>