[ramdisk] add cvitek pre-built ramdisk

Change-Id: Ic7d2046a23358129eaf621b5558984a64fa7361d

ramdisk/initramfs/glibc_riscv64/usr/include/bits/sigstack.h

@@ -0,0 +1,32 @@
+/* sigstack, sigaltstack definitions.
+   Copyright (C) 1998-2019 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef _BITS_SIGSTACK_H
+#define _BITS_SIGSTACK_H 1
+
+#if !defined _SIGNAL_H && !defined _SYS_UCONTEXT_H
+# error "Never include this file directly.  Use <signal.h> instead"
+#endif
+
+/* Minimum stack size for a signal handler.  */
+#define MINSIGSTKSZ	2048
+
+/* System default stack size.  */
+#define SIGSTKSZ	8192
+
+#endif /* bits/sigstack.h */