Include what you use: <fcntl.h>

This was transitively included, but no longer is, so it must be
explicitly included.

Exempt-From-Owner-Approval: Janitorial
Test: build
Change-Id: I1b255b90fe1622e1b64be45e2993a4f0e7d3bcd5
diff --git a/TokenManager.cpp b/TokenManager.cpp
index 378ee16..8c0acfc 100644
--- a/TokenManager.cpp
+++ b/TokenManager.cpp
@@ -18,6 +18,8 @@
 
 #include "TokenManager.h"
 
+#include <fcntl.h>
+
 #include <functional>
 #include <log/log.h>
 #include <openssl/hmac.h>