*: add INSERTs to *.src files where appropriate

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/networking/Kbuild.src b/networking/Kbuild.src
index b0765bc..e1a4ebc 100644
--- a/networking/Kbuild.src
+++ b/networking/Kbuild.src
@@ -5,6 +5,8 @@
 # Licensed under the GPL v2, see the file LICENSE in this tarball.
 
 lib-y:=
+
+INSERT
 lib-$(CONFIG_ARP)          += arp.o interface.o
 lib-$(CONFIG_ARPING)       += arping.o
 lib-$(CONFIG_BRCTL)        += brctl.o