Red Bear OS — microkernel OS in Rust, based on Redox

Derivative of Redox OS (https://www.redox-os.org) adding:
- AMD GPU driver (amdgpu) via LinuxKPI compat layer
- ext4 filesystem support (ext4d scheme daemon)
- ACPI fixes for AMD bare metal (x2APIC, DMAR, IVRS, MCFG)
- Custom branding (hostname, os-release, boot identity)

Build system is full upstream Redox with RBOS overlay in local/.
Patches for kernel, base, and relibc are symlinked from local/patches/
and protected from make clean/distclean. Custom recipes live in
local/recipes/ with symlinks into the recipes/ search path.

Build:  make all CONFIG_NAME=redbear-full
Sync:   ./local/scripts/sync-upstream.sh

recipes/net/rsync/redox.patch

@@ -0,0 +1,25 @@
+diff -ruwN source/rsync.h source-new/rsync.h
+--- source/rsync.h	2025-01-16 02:21:54.000000000 +0700
++++ source-new/rsync.h	2025-09-08 12:18:06.427647717 +0700
+@@ -483,6 +483,21 @@
+ #include <sys/sysmacros.h>
+ #endif
+ 
++#ifdef __redox__
++
++// no sys/sysmacros.h, probably no problem
++#include <sys/types.h>
++#define major(dev) (0)
++#define minor(dev) (0)
++#define makedev(maj, min) (0)
++
++// no openat yet
++#undef O_NOFOLLOW
++#undef O_DIRECTORY
++#undef AT_FDCWD
++
++#endif
++
+ #ifdef MAKEDEV_TAKES_3_ARGS
+ #define MAKEDEV(devmajor,devminor) makedev(0,devmajor,devminor)
+ #else