libc: Move setjmp to libc folder

Now that setjmp() and longjmp() are compliant with the standard they can
be moved with the other libc files.

Change-Id: Iea3b91c34eb353ace5e171e72f331602d57774d5
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
diff --git a/include/lib/libc/setjmp.h b/include/lib/libc/setjmp.h
new file mode 100644
index 0000000..5661201
--- /dev/null
+++ b/include/lib/libc/setjmp.h
@@ -0,0 +1,20 @@
+/*
+ * Copyright (c) 2018-2019, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef SETJMP_H
+#define SETJMP_H
+
+#include <setjmp_.h>
+
+#ifndef __ASSEMBLY__
+
+#include <cdefs.h>
+
+int setjmp(jmp_buf env);
+__dead2 void longjmp(jmp_buf env, int val);
+
+#endif /* __ASSEMBLY__ */
+#endif /* SETJMP_H */