Replace the way to add legacy routing

ConnectivityService is going to become a mainline module which
is not able to access hidden API. Thus, replace the usage from
NMS to INetd.

Bug: 170598012
Test: atest FrameworksNetTests ConnectivityManagerLegacyTest
Change-Id: Ice1bd1effab26555917bc1766354aeaebd41ad66
1 file changed