Updated LocalNetAccessKey to use Type.IpAddress for its
`remoteAddress` BPF field. This enables the BPF map to
store both IPv4 and IPv6 addresses for this key.
To ensure proper functionality with IPv6 addresses, a new
unit test, `testAddLocalNetAccessAfterV_withIPv6`, has been
added to BpfNetMapsTest.java. This test specifically
verifies adding and retrieving local network access rules
using an IPv6 remote address.
Bug: 392509494
Test: atest ConnectivityCoverageTests:android.net.connectivity.com.android.server.BpfNetMapsTest
Flag: EXEMPT refactor
Change-Id: I005f4f2b778ca2d3a4e6578c1440162532f8d004
ab9a3af782