Use SocketKey in MdnsServiceCache

The MdnsServiceTypeClient is now created using a SocketKey, so
the MdnsServiceCache should also use the SocketKey to deal with
the caching services.

Bug: 265787401
Test: atest FrameworksNetTests
Change-Id: I6165ffd420a39e750c06778b4851142a3ba3cf44
2 files changed