Fixed Android build error
diff --git a/src/hidapi/android/hid.cpp b/src/hidapi/android/hid.cpp
index 0a8a777..37b159b 100644
--- a/src/hidapi/android/hid.cpp
+++ b/src/hidapi/android/hid.cpp
@@ -10,6 +10,7 @@
#include <android/log.h>
#include <pthread.h>
#include <errno.h> // For ETIMEDOUT and ECONNRESET
+#include <stdlib.h> // For malloc() and free()
#define TAG "hidapi"
#ifdef DEBUG