cleanup - config_item_int16() & DEFAULT_IPV4_LOCAL_PREFIXLEN

Test:
  git grep 'config_item_int16|DEFAULT_IPV4_LOCAL_PREFIXLEN'
  comes up empty

Bug: 144730808
Test: atest clatd_test netd_integration_test
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Change-Id: I71716cdcba382bc5fb1efa5000189f63a57015c9
2 files changed