Fix Visual Studio .NET 2003 compatibility

Apparently `errno_t` doesn't exist here either?

miniaudio.h

@@ -6781,7 +6781,7 @@ static ma_result ma_result_from_errno(int e)
 
 MA_API ma_result ma_fopen(FILE** ppFile, const char* pFilePath, const char* pOpenMode)
 {
-#if _MSC_VER && _MSC_VER >= 1300
+#if _MSC_VER && _MSC_VER >= 1400
     errno_t err;
 #endif
 
@@ -6793,7 +6793,7 @@ MA_API ma_result ma_fopen(FILE** ppFile, const char* pFilePath, const char* pOpe
         return MA_INVALID_ARGS;
     }
 
-#if _MSC_VER && _MSC_VER >= 1300
+#if _MSC_VER && _MSC_VER >= 1400
     err = fopen_s(ppFile, pFilePath, pOpenMode);
     if (err != 0) {
         return ma_result_from_errno(err);