sys-apps/systemd: Sync with Gentoo

It's from Gentoo commit 473b0997ba121fcc629f94a480238f8e664f900d

sdk_container/src/third_party/coreos-overlay/sys-apps/systemd/Manifest

@@ -1 +1 @@
-DIST systemd-stable-255.8.tar.gz 15070471 BLAKE2B b437404af7fd73ef527f80d9d14d46a781444103d1756c27494ecf2664c9c5efe1169c85b91148a3bf190dc7c5e31cf8d42a13c84102d101ea7e4a0570e8d719 SHA512 7692be761a393924669a90f6f343998a85707a9daa3ce169ce67f62ae2a39338c2c3496066b2659c6500849104fab0529fca5704a3eb32375f2f44131216d1f1
+DIST systemd-256.7.tar.gz 15672532 BLAKE2B d718b7bcbf9c3583953a9fa82319f04b32d17c5b7539a49b9999881bd8cea7fd9a06f252d763170613a6cd0fd2535762b233cba74eb87764f662c4bdf2d8c1da SHA512 2ff3805a7d97780a716b23ddeea3722a85aba6326ecee527e53e9d35510a0ffa5ec0bf0cdbf8f3409bb9c6832406916f63eb7e8305db5f67c284e5590c642422

sdk_container/src/third_party/coreos-overlay/sys-apps/systemd/files/256-bpf-gcc.patch

@@ -0,0 +1,26 @@
+https://github.com/systemd/systemd/commit/dde6f1d7456db7aa72d24b1d6956b419b6f9945c
+
+From dde6f1d7456db7aa72d24b1d6956b419b6f9945c Mon Sep 17 00:00:00 2001
+From: Sam James <sam@gentoo.org>
+Date: Sat, 24 Aug 2024 13:09:47 +0100
+Subject: [PATCH] meson: search for 'bpf-unknown-none' too
+
+We currently search for 'bpf-gcc' and 'bpf-none-gcc'. Gentoo's
+sys-devel/bpf-toolchain package uses 'bpf-unknown-none-gcc', as does Fedora's
+cross-binutils. Search for this name too.
+---
+ meson.build | 1 +
+ 1 file changed, 1 insertion(+)
+
+diff --git a/meson.build b/meson.build
+index 5e0b666c64b17..fbc2bbdf2f22f 100644
+--- a/meson.build
++++ b/meson.build
+@@ -1109,6 +1109,7 @@ else
+         elif bpf_compiler == 'gcc'
+                 bpf_gcc = find_program('bpf-gcc',
+                                        'bpf-none-gcc',
++                                       'bpf-unknown-none-gcc',
+                                        required : true,
+                                        version : '>= 13.1.0')
+                 bpf_gcc_found = bpf_gcc.found()