Add more test coverage for /etc/hosts lookup

Sadly, there are two distinct parsers for the hosts file: one used by
getaddrinfo() and one used by the legacy gethostbyname() & friends.
These tests cover the latter.

Test: m netd, sync system, atest netd_integration_test
Change-Id: I1d35ae594b25684d69b6ca4864e8cc5547f7b4de
1 file changed