cmake: set CMP0066 => NEW

CMakeLists.txt

@@ -56,6 +56,10 @@ if(POLICY CMP0056)
   cmake_policy(SET CMP0056 NEW)  # try_compile(): link flags
 endif()
 
+if(POLICY CMP0066)
+  cmake_policy(SET CMP0066 NEW)  # CMake 3.7: try_compile(): use per-config flags, like CMAKE_CXX_FLAGS_RELEASE
+endif()
+
 if(POLICY CMP0067)
   cmake_policy(SET CMP0067 NEW)  # CMake 3.8: try_compile(): honor language standard variables (like C++11)
 endif()