Add the MU (message unit) driver and IPC functions for communicating with SCFW.
Add CONFIG_HAVE_SC_FIRMWARE for enabling the IPC feature and holding the
IP channel in global data.
Signed-off-by: Ranjani Vaidyanathan <Ranjani.Vaidyanathan@nxp.com>
Signed-off-by: Ye Li <ye.li@nxp.com>
Ye Li