Link in the logging library, for __android_log_write.

In preparation for a larger change that will start using that function.

Test: code still builds and has size 270.0K, as before.

To build it, I'm using
mmma -j16 external/libtextclassifier

Change-Id: I815f0fc728f43f729fbd47a8b4f021b4902e6702