fix the static lib don't work on MinGW

Author: Shao-Feng

mingw_cross_toolchain.cmake

@@ -11,3 +11,8 @@ SET(CMAKE_FIND_ROOT_PATH  /usr/${GNU_HOST} /home/joey/workspace/testkit-lite/sha
 set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)
 set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
 set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)
+
+set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -static-libgcc")
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -static-libgcc -static-libstdc++")
+set(CMAKE_SHARED_LIBRARY_LINK_C_FLAGS "${CMAKE_SHARED_LIBRARY_LINK_C_FLAGS} -static-libgcc -s")
+set(CMAKE_SHARED_LIBRARY_LINK_CXX_FLAGS "${CMAKE_SHARED_LIBRARY_LINK_CXX_FLAGS} -static-libgcc -static-libstdc++ -s")