BuildSystem: Move all userpace libraries under the userspace directory

As the number of libraries is increasing, root directory starts to
expand. This adds better organization for libraries

userspace/libraries/LibC/include/sys/ipc.h

@@ -0,0 +1,37 @@
+#ifndef _SYS_IPC_H
+#define _SYS_IPC_H 1
+
+// https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/sys_ipc.h.html
+
+#include <sys/cdefs.h>
+
+__BEGIN_DECLS
+
+#define __need_uid_t
+#define __need_gid_t
+#define __need_mode_t
+#define __need_key_t
+#include <sys/types.h>
+
+struct ipc_perm
+{
+	uid_t	uid;	/* Owner's user ID. */
+	gid_t	gid;	/* Owner's group ID. */
+	uid_t	cuid;	/* Creator's user ID. */
+	gid_t	cgid;	/* Creator's group ID. */
+	mode_t	mode;	/* Read/write permission. */
+};
+
+#define IPC_CREAT	0x01
+#define IPC_EXCL	0x02
+#define IPC_NOWAIT	0x04
+#define IPC_PRIVATE	0x08
+#define IPC_RMID	0x10
+#define IPC_SET		0x20
+#define IPC_STAT	0x40
+
+key_t ftok(const char* path, int id);
+
+__END_DECLS
+
+#endif