Log Message:
logswan: update to 2.1.2.

Logswan 2.1.2 (2019-11-19)

- Add ENABLE_SECCOMP build option, to allow building seccomp support
  conditionally
- Disable seccomp by default, it needs more testing on non !amd64 platforms
- Use ${CMAKE_INSTALL_BINDIR} instead of hardcoding 'bin'