Add utility functions to neighbour_test.

1. Clear the ND cache entries for the IPv6 routers before each
   test, so we can add tests and always start from a clean slate.
2. Support expecting multicast NS.
3. Support generating NAs with different source and destination
   addresses.

Change-Id: I9f8bb37540efa2d237eb236059e859f42aacdadc
1 file changed
tree: 11a271d9b3dc27b1f4b1ccc904d4c37e601c2992
  1. net/