Update CMakeLists.txt

Enable check for OpenMP-support.

CMakeLists.txt

@@ -145,6 +145,13 @@ IF(ASSIMP_DOUBLE_PRECISION)
   ADD_DEFINITIONS(-DASSIMP_DOUBLE_PRECISION)
 ENDIF(ASSIMP_DOUBLE_PRECISION)
 
+# Check for OpenMP support
+find_package(OpenMP)
+if (OPENMP_FOUND)
+    set (CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${OpenMP_C_FLAGS}")
+    set (CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${OpenMP_CXX_FLAGS}")
+endif()
+
 configure_file(
   ${CMAKE_CURRENT_LIST_DIR}/revision.h.in
   ${CMAKE_CURRENT_BINARY_DIR}/revision.h