Fix typo in platform_util.c

Fix a typo in a conditional include.

Signed-off-by: Michael Grand (TrustnGo) <m.grand@trustngo.tech>
diff --git a/library/platform_util.c b/library/platform_util.c
index 0741bf5..19ef07a 100644
--- a/library/platform_util.c
+++ b/library/platform_util.c
@@ -149,7 +149,7 @@
 #include <time.h>
 #if !defined(_WIN32) && (defined(unix) || \
     defined(__unix) || defined(__unix__) || (defined(__APPLE__) && \
-    defined(__MACH__)) || defined__midipix__)
+    defined(__MACH__)) || defined(__midipix__))
 #include <unistd.h>
 #endif /* !_WIN32 && (unix || __unix || __unix__ ||
         * (__APPLE__ && __MACH__) || __midipix__) */