Remove the notion of "sys*"

- This idea originates from very early in the project and was, at the
  time, a very easy way to categorise things.
- Now, it doesn't really make much sense - it is fairly arbitary, often
  occuring when there is a change in kernel, but not from builder-hex0
  to fiwix, and sysb is in reality completely unnecessary.
- In short, the sys* stuff is a bit of a mess that makes the project
  more difficult to understand.
- This puts everything down into one folder and has a manifest file that
  is used to generate the build scripts on the fly rather than using
  coded scripts.
- This is created in the "seed" stage.

stage0-posix -- (calls) --> seed -- (generates) --> main steps

Alongside this change there are a variety of other smaller fixups to the
general structure of the live-bootstrap rootfs.

- Creating a rootfs has become much simpler and is defined as code in
  go.sh. The new structure, for an about-to-be booted system, is

/
-- /steps (direct copy of steps/)
-- /distfiles (direct copy of distfiles/)
-- all files from seed/*
-- all files from seed/stage0-posix/*

- There is no longer such a thing as /usr/include/musl, this didn't
  really make any sense, as musl is the final libc used. Rather, to
  separate musl and mes, we have /usr/include/mes, which is much easier
  to work with.
- This also makes mes easier to blow away later.
- A few things that weren't properly in packages have been changed;
  checksum-transcriber, simple-patch, kexec-fiwix have all been given
  fully qualified package names.
- Highly breaking change, scripts now exist in their package directory
  but NOT WITH THE packagename.sh. Rather, they use pass1.sh, pass2.sh,
  etc. This avoids manual definition of passes.
  - Ditto with patches; default directory is patches, but then any patch
    series specific to a pass are named patches-passX.

sysc/gcc-4.7.4/patches/0006-add-musl-support-to-gcc.patch

@@ -1,69 +0,0 @@
-SPDX-FileCopyrightText: 2022 Dor Askayo <dor.askayo@gmail.com>
-SPDX-FileCopyrightText: 2015 Szabolcs Nagy <szabolcs.nagy@arm.com>
-
-SPDX-License-Identifier: GPL-2.0-or-later
-
-Backported from upstream commit 07ad804bfdbe0fa3406c5f2ff51d7c4c29a783c8
-
-Add musl support to GCC
-
-2015-05-08  Szabolcs Nagy  <szabolcs.nagy@arm.com>
-
-	* config/glibc-stdint.h (OPTION_MUSL): Define.
-	(INT_FAST16_TYPE, INT_FAST32_TYPE, UINT_FAST16_TYPE, UINT_FAST32_TYPE):
-	Change the definition based on OPTION_MUSL for 64 bit targets.
-	* config/linux.h (OPTION_MUSL): Redefine.
-	* config/alpha/linux.h (OPTION_MUSL): Redefine.
-	* config/rs6000/linux.h (OPTION_MUSL): Redefine.
-	* config/rs6000/linux64.h (OPTION_MUSL): Redefine.
-
-From-SVN: r222905
-
---- gcc/config/glibc-stdint.h
-+++ gcc/config/glibc-stdint.h
-@@ -22,6 +22,12 @@ a copy of the GCC Runtime Library Exception along with this program;
- see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
- <http://www.gnu.org/licenses/>.  */
- 
-+/* Systems using musl libc should use this header and make sure
-+   OPTION_MUSL is defined correctly before using the TYPE macros. */
-+#ifndef OPTION_MUSL
-+#define OPTION_MUSL 0
-+#endif
-+
- #define SIG_ATOMIC_TYPE "int"
- 
- #define INT8_TYPE "signed char"
-@@ -43,12 +49,12 @@ see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
- #define UINT_LEAST64_TYPE (LONG_TYPE_SIZE == 64 ? "long unsigned int" : "long long unsigned int")
- 
- #define INT_FAST8_TYPE "signed char"
--#define INT_FAST16_TYPE (LONG_TYPE_SIZE == 64 ? "long int" : "int")
--#define INT_FAST32_TYPE (LONG_TYPE_SIZE == 64 ? "long int" : "int")
-+#define INT_FAST16_TYPE (LONG_TYPE_SIZE == 64 && !OPTION_MUSL ? "long int" : "int")
-+#define INT_FAST32_TYPE (LONG_TYPE_SIZE == 64 && !OPTION_MUSL ? "long int" : "int")
- #define INT_FAST64_TYPE (LONG_TYPE_SIZE == 64 ? "long int" : "long long int")
- #define UINT_FAST8_TYPE "unsigned char"
--#define UINT_FAST16_TYPE (LONG_TYPE_SIZE == 64 ? "long unsigned int" : "unsigned int")
--#define UINT_FAST32_TYPE (LONG_TYPE_SIZE == 64 ? "long unsigned int" : "unsigned int")
-+#define UINT_FAST16_TYPE (LONG_TYPE_SIZE == 64 && !OPTION_MUSL ? "long unsigned int" : "unsigned int")
-+#define UINT_FAST32_TYPE (LONG_TYPE_SIZE == 64 && !OPTION_MUSL ? "long unsigned int" : "unsigned int")
- #define UINT_FAST64_TYPE (LONG_TYPE_SIZE == 64 ? "long unsigned int" : "long long unsigned int")
- 
- #define INTPTR_TYPE (LONG_TYPE_SIZE == 64 ? "long int" : "int")
---- gcc/config/linux.h
-+++ gcc/config/linux.h
-@@ -33,11 +33,13 @@ see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
- #define OPTION_GLIBC  (DEFAULT_LIBC == LIBC_GLIBC)
- #define OPTION_UCLIBC (DEFAULT_LIBC == LIBC_UCLIBC)
- #define OPTION_BIONIC (DEFAULT_LIBC == LIBC_BIONIC)
-+#undef OPTION_MUSL
- #define OPTION_MUSL   (DEFAULT_LIBC == LIBC_MUSL)
- #else
- #define OPTION_GLIBC  (linux_libc == LIBC_GLIBC)
- #define OPTION_UCLIBC (linux_libc == LIBC_UCLIBC)
- #define OPTION_BIONIC (linux_libc == LIBC_BIONIC)
-+#undef OPTION_MUSL
- #define OPTION_MUSL   (linux_libc == LIBC_MUSL)
- #endif
-