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/errno.h

@@ -0,0 +1,102 @@
+#ifndef _ERRNO_H
+#define _ERRNO_H 1
+
+// https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/errno.h.html
+
+#include <sys/cdefs.h>
+
+__BEGIN_DECLS
+
+#define E2BIG			1
+#define EACCES			2
+#define EADDRINUSE		3
+#define EADDRNOTAVAIL	4
+#define EAFNOSUPPORT	5
+#define EAGAIN			6
+#define EALREADY		7
+#define EBADF			8
+#define EBADMSG			9
+#define EBUSY			10
+#define ECANCELED		11
+#define ECHILD			12
+#define ECONNABORTED	13
+#define ECONNREFUSED	14
+#define ECONNRESET		15
+#define EDEADLK			16
+#define EDESTADDRREQ	17
+#define EDOM			18
+#define EDQUOT			19
+#define EEXIST			20
+#define EFAULT			21
+#define EFBIG			22
+#define EHOSTUNREACH	23
+#define EIDRM			24
+#define EILSEQ			25
+#define EINPROGRESS		26
+#define EINTR			27
+#define EINVAL			28
+#define EIO				29
+#define EISCONN			30
+#define EISDIR			31
+#define ELOOP			32
+#define EMFILE			33
+#define EMLINK			34
+#define EMSGSIZE		35
+#define EMULTIHOP		36
+#define ENAMETOOLONG	37
+#define ENETDOWN		38
+#define ENETRESET		39
+#define ENETUNREACH		40
+#define ENFILE			41
+#define ENOBUFS			42
+#define ENODATA			43
+#define ENODEV			44
+#define ENOENT			45
+#define ENOEXEC			46
+#define ENOLCK			47
+#define ENOLINK			48
+#define ENOMEM			49
+#define ENOMSG			50
+#define ENOPROTOOPT		51
+#define ENOSPC			52
+#define ENOSR			53
+#define ENOSTR			54
+#define ENOSYS			55
+#define ENOTCONN		56
+#define ENOTDIR			57
+#define ENOTEMPTY		58
+#define ENOTRECOVERABLE	59
+#define ENOTSOCK		60
+#define ENOTSUP			61
+#define ENOTTY			62
+#define ENXIO			63
+#define EOPNOTSUPP		64
+#define EOVERFLOW		65
+#define EOWNERDEAD		66
+#define EPERM			67
+#define EPIPE			68
+#define EPROTO			69
+#define EPROTONOSUPPORT	70
+#define EPROTOTYPE		71
+#define ERANGE			72
+#define EROFS			73
+#define ESPIPE			74
+#define ESRCH			75
+#define ESTALE			76
+#define ETIME			77
+#define ETIMEDOUT		78
+#define ETXTBSY			79
+#define EWOULDBLOCK		80
+#define EXDEV			81
+#define ENOTBLK			82
+#define EEXISTS			83
+
+#define EUNKNOWN		0xFF
+
+#define errno __errno
+
+extern int __errno;
+
+__END_DECLS
+
+#endif