remove unnecessary exclusion for Windows which was killing the Windows nightly build

This commit was SVN r5695.

src/threads/condition.c

@@ -37,9 +37,7 @@ static void ompi_condition_destruct(ompi_condition_t *c)
 #endif
 }
 
-#ifndef WIN32
 OBJ_CLASS_INSTANCE(ompi_condition_t,
                    ompi_object_t,
                    ompi_condition_construct,
                    ompi_condition_destruct);
-#endif