Fixup netlink socket creation to make corresponding fix in JNI

Corresponding JNI fix is:

    aosp/516339
    oc-mr1-dev:3102743

Test: as follows
    - built
    - flashed
    - booted
    - make vts -j30 BUILD_GOOGLE_VTS=true && \
      vts-tradefed run commandAndExit vts --skip-all-system-status-check --primary-abi-only --skip-preconditions --module VtsHalTetherOffloadControlV1_0Target -l DEBUG

      10-20 17:48:28 I/ResultReporter: Invocation finished in 5m 32s. PASSED: 38, FAILED: 0, MODULES: 1 of 1

Bug: 68018148

Change-Id: I5aa019d708abaff61387b83a857e9e8226709842