Make sure ibrcommon was build with ssl support

If you build ibrdtn with libssl-dev and libgnutls-dev on your system and you do not configure ibrdtn with "--with-openssl" the make process will fail.

E.g. https://github.com/bgernert/ibrdtn/blob/master/ibrdtn/daemon/src/NativeDaemon.cpp#L1010-L1017 will fail because WITH_TLS will be set to TRUE but dtn::security::SecurityCertificateManager() won't be available (because security will only build if the --with-openssl flag is given). There are some more errors in the TCP convergence layer.