userspace: Introduce userspace proxy and user worker to service IPC

The non-privileged modules code should be executed in separate thread
executed in userspace mode. This way the code and data owned by such
module will be isolated from other non-privileged modules in the system.

The implementation creates user_work_queue threads that will service all
IPC's for all such modules. There are security domains defined that will
combines service of IPC's for modules that could exist without isolation
(eg. several instances of the same module or modules originating from single
vendor).

Signed-off-by: Jaroslaw Stelter <Jaroslaw.Stelter@intel.com>
Signed-off-by: Adrian Warecki <adrian.warecki@intel.com>

Author: jxstelter

src/audio/module_adapter/CMakeLists.txt

@@ -42,6 +42,12 @@ if(zephyr) ###  Zephyr ###
 		library/native_system_service.c
 	)
 
+	if(CONFIG_USERSPACE)
+		zephyr_library_sources_ifdef(CONFIG_INTEL_MODULES
+			library/userspace_proxy.c
+		)
+	endif()
+
 	zephyr_library_sources_ifdef(CONFIG_PASSTHROUGH_CODEC
 		module/passthrough.c
 	)