init: apply routing to environment sessions

The init component used to create the CPU/RAM/PD/ROM sessions (the child
environment) for its children by issuing session requests to its parent,
which is typically core. This policy was hard-wired. This patch enables
the routing of the environment sessions of the children of init
according to the configured routing policy.

Because there is no hard-wired policy regarding the environment sessions
anymore, routes to respective services must be explicitly declared in
the init configuration. For this reason, the patch adjusts several run
scripts in this respect.

This patch removes the outdated '<if-args>' special handling of session
labels. The '<if-args>' feature will eventually be removed completely
(ref #2250)

Issue #2197
Issue #2215
Issue #2233
Issue #2250

repos/base-linux/run/lx_hybrid_exception.run

@@ -23,6 +23,9 @@ install_config {
 	<config>
 		<parent-provides>
 			<service name="ROM"/>
+			<service name="RAM"/>
+			<service name="CPU"/>
+			<service name="PD"/>
 			<service name="LOG"/>
 		</parent-provides>
 		<default-route>