OpenBSD doesn't support pthread_condattr_setpshared

Index: DPF/distrho/extra/Mutex.hpp
--- DPF/distrho/extra/Mutex.hpp.orig
+++ DPF/distrho/extra/Mutex.hpp
@@ -196,7 +196,9 @@ class Signal (public)
     {
         pthread_condattr_t cattr;
         pthread_condattr_init(&cattr);
+#if 0
         pthread_condattr_setpshared(&cattr, PTHREAD_PROCESS_PRIVATE);
+#endif
         pthread_cond_init(&fCondition, &cattr);
         pthread_condattr_destroy(&cattr);
 
