more precise MSVC specification

Author: jackoalan

CMakeLists.txt

@@ -18,7 +18,7 @@ set(ATHENA_VERSION
 add_subdirectory(extern)
 
 include_directories(include ${LZO_INCLUDE_DIR} ${ZLIB_INCLUDE_DIR})
-if (NOT WIN32)
+if (NOT MSVC)
 set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")
 endif()
 
@@ -110,7 +110,7 @@ add_library(AthenaWiiSave
     include/md5.h
     include/sha1.h
 )
-if(NOT WIN32)
+if(NOT MSVC)
 set_source_files_properties(src/aes.cpp PROPERTIES COMPILE_FLAGS -maes)
 endif()