Complete Haiku platform support. (#10311)

Fixing linkage/libraries missing issue.
Implements missing platform specifics.

src/threading/thread.cpp

@@ -225,6 +225,10 @@ void Thread::setName(const std::string &name)
 
 	pthread_setname_np(name.c_str());
 
+#elif defined(__HAIKU__)
+
+	rename_thread(find_thread(NULL), name.c_str());
+
 #elif defined(_MSC_VER)
 
 	// Windows itself doesn't support thread names,

src/threading/thread.h

@@ -36,6 +36,10 @@ DEALINGS IN THE SOFTWARE.
 	#include <sys/thread.h> // for tid_t
 #endif
 
+#ifdef __HAIKU__
+	#include <kernel/OS.h>
+#endif
+
 /*
  * On platforms using pthreads, these five priority classes correlate to
  * even divisions between the minimum and maximum reported thread priority.