Choose the right LIB_SPEC for threads based on "__FreeBSD_version". This allows someone with an older -current to update their compiler [only].
Choose the right LIB_SPEC for threads based on "__FreeBSD_version".
This allows someone with an older -current to update their compiler [only].

Inspired by:	Loren James Rittle <rittle@rsch.comm.mot.com>

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase