move ipm.h to drivers/ipm.h and
create a shim for backward-compatibility.
No functional changes to the headers.
A warning in the shim can be controlled with CONFIG_COMPAT_INCLUDES.
Related to #16539
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
Add driver for i.MX Messaging Unit peripheral which can be used for
i.MX6SoloX, i.MX7D and other i.MX socs.
Origin: Original
Signed-off-by: Stanislav Poboril <stanislav.poboril@nxp.com>