[CLATJ#32] ClatCoordinator: untag clat raw socket

Untag clat raw socket while stopping clatd.

Bug: 218407445
Test: atest FrameworksNetTests
Test: connect and disconnect to/from IPv6 only network
Check dumpsys tag map and logging for tagging/untagging socket
03-04 16:29:17.247  1330  1714 I jniClatCoordinator: tag uid AID_CLAT to socket fd 420, cookie 16524
03-04 16:29:31.343  1330  1714 I jniClatCoordinator: untag socket cookie 16524

Change-Id: Id5f5bdfc97a15abfa1a49b06dcb3c2c25743c74f
3 files changed