DHCP: Move the packet code to frameworks/base/services.

There's no need for it to be in frameworks/base/core, since it
will only be used by services.

Bug: 19704592
Change-Id: I2f5277eca848b7000ca46db575e8602eacb5c8bd
diff --git a/services/Android.mk b/services/Android.mk
index da85528..8777085 100644
--- a/services/Android.mk
+++ b/services/Android.mk
@@ -24,6 +24,7 @@
     appwidget \
     backup \
     devicepolicy \
+    net \
     print \
     restrictions \
     usage \