build: Use Threads_FOUND to decide whether to build ssh_threads.

Follow-up to 4e04ec8, which caused a regression on OS X.

Checking the value of CMAKE_THREAD_LIBS_INIT to decide whether any threading
library is present on a system turns out to be wrong -- in OS X, for
example, usage of pthreads does not depend on any additional linker or
compiler flags, so CMAKE_THREAD_LIBS_INIT is empty and our check in
src/CMakeLists.txt failed (it used to work before 4e04ec8 because
CMAKE_HAVE_THREADS_LIBRARY is set).

Instead, just look for Threads_FOUND, which FindThreads sets just like any
other Find module when it has found what it was looking for.

Reviewed-by: Andreas Schneider <asn@cryptomilk.org>

0 files changed, 0 insertions, 0 deletions