Fix for -pthread in DragonFly

Hi all,

due to recent changes in DragonFly's /usr/lib layout clang's -pthread was broken. Attached patch fixes this. The previous code was wrong anyways because it ignored the user selected thread lib.

Regards,
Sascha

dfly_tools.diff (445 Bytes)

Re-submit of my patch, now relative to tools/clang.

Regards,
Sascha

dfly_tools.diff (409 Bytes)

Applied, thanks!