Revert "Remove gmp from AOS"

This reverts commit f37c97684f0910a3f241394549392f00145ab0f7.

We need gmp for SymEngine for symbolicmanipultion in C++

Change-Id: Ia13216d1715cf96944f7b4f422b7a799f921d4a4
Signed-off-by: Austin Schuh <austin.linux@gmail.com>
diff --git a/third_party/gmp/demos/calc/calc-common.h b/third_party/gmp/demos/calc/calc-common.h
new file mode 100644
index 0000000..7a91878
--- /dev/null
+++ b/third_party/gmp/demos/calc/calc-common.h
@@ -0,0 +1,35 @@
+/* Prototypes etc for calc program.
+
+Copyright 2001 Free Software Foundation, Inc.
+
+This file is part of the GNU MP Library.
+
+This program is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free Software
+Foundation; either version 3 of the License, or (at your option) any later
+version.
+
+This program is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
+PARTICULAR PURPOSE.  See the GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License along with
+this program.  If not, see https://www.gnu.org/licenses/.  */
+
+#include <stddef.h>  /* for size_t */
+#ifndef NO_CALC_H
+#include "calc.h"
+#endif
+#include "calc-config.h"
+
+struct calc_keywords_t {
+  char  *name;
+  int   value;
+};
+
+extern int  calc_option_readline;
+extern int  calc_more_input;
+extern const struct calc_keywords_t  calc_keywords[];
+
+int calc_input (char *buf, size_t max_size);
+void calc_init_readline (void);