cpp: use #ifdef __MINGW32__ to avoid compiler complaints

... instead of just #if

diff --git a/tests/server/util.c b/tests/server/util.c
index 8158cb2914e3fec06e5ae2f44ca7d89a91a71cbb..bd65428265652dc51835331f4c016b0dc0fe4fd7 100644 (file)
--- a/tests/server/util.c
+++ b/tests/server/util.c
@@ -55,7 +55,7 @@
 #define EINVAL  22 /* errno.h value */
 #endif
 
-#if __MINGW32__
+#ifdef __MINGW32__
 #include <TlHelp32.h>
 #endif