[RN#9] make clatd functions return -errno

For consistent, return -errno but errno on failure.

Changed functions:
- configure_tun_ip
- detect_mtu
- configure_clat_ipv6_address
- configure_packet_socket
- add_anycast_address

Also fix a return errno bug in configure_tun_ip(),
InterfaceController::setMtu has already returned -errno.

Bug: 212345928
Test: atest ClatdControllerTest
Change-Id: I105d5b0c67a881970a6534fb26878f3af8242e08
1 file changed
tree: e51af1f4eed532b6efe3cc4ca70fab4ee7d54794
  1. bpf_progs/
  2. client/
  3. include/
  4. libnetdbpf/
  5. netutils_wrappers/
  6. server/
  7. tests/
  8. .editorconfig
  9. Android.bp
  10. NOTICE
  11. OWNERS
  12. PREUPLOAD.cfg
  13. TEST_MAPPING