Move host library name back to libevent-host.so

There is an argument that this prevents us from using a system provided
library when we intended to use our own. The build system now supports
'unique_host_soname: true' to automatically do this renaming for host
libraries, while still using 'libevent' as the reference within the
build files.

Change-Id: Iefbb7b8f46dbe951d05d9bda262af7998bbc6929
1 file changed