modules-avb: Introducing entity builder. The entity builder is necessary

to attach ressource to the descriptors instead of having them splitted.

It is the case for the avb-streams which in a seperated list. Instead they
should be encapsulated within the descriptor itself, as one cannot leave
without the other.

src/modules/meson.build

@@ -736,6 +736,7 @@ if build_module_avb
       'module-avb/acmp.c',
       'module-avb/aecp.c',
       'module-avb/aecp-aem.c',
+      'module-avb/es-builder.c',
       'module-avb/avdecc.c',
       'module-avb/maap.c',
       'module-avb/mmrp.c',