Fix CMake variables

Fix CMake variables

[Bug]           * systemd service/socket files should be in /usr/local/lib, while
                  compiled libraries should reside in /usr/local/lib64 on 64-bit
                  systems.
                * Two sockets were created - one by systemd service, one by vasum
                  IPC mechanisms.
[Cause]         N/A
[Solution]      Rename vasum-ipc.socket to vasum.socket
                Correct variables regarding library and systemd file locations
[Verification]  Build, install, run tests, run vasum-cli, check file locations and
                service files.

Change-Id: I54681eaebd00b1aec547617a2ea51b0675c24ec3