SunPro: add standard compile option for C++03

Modules/Compiler/SunPro-CXX.cmake

@@ -37,8 +37,8 @@ set(CMAKE_CXX_CREATE_STATIC_LIBRARY
   "<CMAKE_RANLIB> <TARGET> ")
 
 if (NOT CMAKE_CXX_COMPILER_VERSION VERSION_LESS 5.13)
-  set(CMAKE_CXX98_STANDARD_COMPILE_OPTION "")
-  set(CMAKE_CXX98_EXTENSION_COMPILE_OPTION "")
+  set(CMAKE_CXX98_STANDARD_COMPILE_OPTION "-std=c++03")
+  set(CMAKE_CXX98_EXTENSION_COMPILE_OPTION "-std=c++03")
   set(CMAKE_CXX11_STANDARD_COMPILE_OPTION "-std=c++11")
   set(CMAKE_CXX11_EXTENSION_COMPILE_OPTION "-std=c++11")
   set(CMAKE_CXX_LINK_WITH_STANDARD_COMPILE_OPTION 1)