init: use rvalues references for callees of ParseLineSection()

ParseLineSection() provides 'args' as an rvalue reference, so its
callers can and should use it as such.  This saves some copying
overhead and cleans up the code a bit.

Test: boot
Change-Id: Ib906318583dc81de9ea585f5f09fdff35403be1b
diff --git a/init/action.h b/init/action.h
index 4f063cc..967c682 100644
--- a/init/action.h
+++ b/init/action.h
@@ -36,7 +36,7 @@
 
 class Command {
   public:
-    Command(BuiltinFunction f, bool execute_in_subcontext, const std::vector<std::string>& args,
+    Command(BuiltinFunction f, bool execute_in_subcontext, std::vector<std::string>&& args,
             int line);
 
     Result<Success> InvokeFunc(Subcontext* subcontext) const;
@@ -61,8 +61,8 @@
            const std::string& event_trigger,
            const std::map<std::string, std::string>& property_triggers);
 
-    Result<Success> AddCommand(const std::vector<std::string>& args, int line);
-    void AddCommand(BuiltinFunction f, const std::vector<std::string>& args, int line);
+    Result<Success> AddCommand(std::vector<std::string>&& args, int line);
+    void AddCommand(BuiltinFunction f, std::vector<std::string>&& args, int line);
     std::size_t NumCommands() const;
     void ExecuteOneCommand(std::size_t command) const;
     void ExecuteAllCommands() const;