Never use %zu on MinGW

Signed-off-by: Bence Szépkúti <bence.szepkuti@arm.com>
diff --git a/include/mbedtls/debug.h b/include/mbedtls/debug.h
index a940ef7..8e1bd83 100644
--- a/include/mbedtls/debug.h
+++ b/include/mbedtls/debug.h
@@ -108,7 +108,7 @@
  *
  * This module provides debugging functions.
  */
-#if (defined(__MINGW32__) && __USE_MINGW_ANSI_STDIO == 0) || (defined(_MSC_VER) && _MSC_VER < 1900)
+#if defined(__MINGW32__) || (defined(_MSC_VER) && _MSC_VER < 1900)
    #include <inttypes.h>
    #define MBEDTLS_PRINTF_SIZET     PRIuPTR
    #define MBEDTLS_PRINTF_LONGLONG  "I64d"