Include thread tests in CMake.

Tools/CMake/torque3d.cmake

@@ -200,6 +200,7 @@ if( NOT TORQUE_DEDICATED )
 endif()
 addPath("${srcDir}/platform/test")
 addPath("${srcDir}/platform/threads")
+addPath("${srcDir}/platform/threads/test")
 addPath("${srcDir}/platform/async")
 addPath("${srcDir}/platform/async/test")
 addPath("${srcDir}/platform/input")