deps: add missing ares_android.h file

deps/cares/src/ares_android.h

@@ -0,0 +1,26 @@
+/* Copyright (C) 2017 by John Schember <john@nachtimwald.com>
+ *
+ * Permission to use, copy, modify, and distribute this
+ * software and its documentation for any purpose and without
+ * fee is hereby granted, provided that the above copyright
+ * notice appear in all copies and that both that copyright
+ * notice and this permission notice appear in supporting
+ * documentation, and that the name of M.I.T. not be used in
+ * advertising or publicity pertaining to distribution of the
+ * software without specific, written prior permission.
+ * M.I.T. makes no representations about the suitability of
+ * this software for any purpose.  It is provided "as is"
+ * without express or implied warranty.
+ */
+
+#ifndef __ARES_ANDROID_H__
+#define __ARES_ANDROID_H__
+
+#if defined(ANDROID) || defined(__ANDROID__)
+
+char **ares_get_android_server_list(size_t max_servers, size_t *num_servers);
+void ares_library_cleanup_android(void);
+
+#endif
+
+#endif /* __ARES_ANDROID_H__ */