sys-apps/systemd: add v256.5 with musl libc patches

- https://code.atwilcox.tech/sphen/scaly/systemd
- https://catfox.life/2024/09/05/porting-systemd-to-musl-libc-powered-linux/

sys-apps/systemd/files/0016-test-Handle-musl-s-interesting-locale-decisions.patch

@@ -0,0 +1,53 @@
+From 61770e8d6c24c01d6a0e35518ba16ec8d4fa8e6a Mon Sep 17 00:00:00 2001
+From: "A. Wilcox" <AWilcox@Wilcox-Tech.com>
+Date: Sun, 18 Aug 2024 02:53:59 -0500
+Subject: [PATCH 16/34] test: Handle musl's interesting locale decisions
+Content-Type: text/plain; charset="utf-8"
+Content-Transfer-Encoding: 8bit
+
+All locales exist!  But they don't do anything!
+
+This cannot be upstreamed.  And some day, this should be dropable.
+
+Signed-off-by: Alexander Miroshnichenko <alex@millerson.name>
+---
+ src/test/test-locale-util.c | 2 +-
+ src/test/test-parse-util.c  | 2 ++
+ 2 files changed, 3 insertions(+), 1 deletion(-)
+
+diff --git a/src/test/test-locale-util.c b/src/test/test-locale-util.c
+index ab2d1f5746cf..9c95debcae35 100644
+--- a/src/test/test-locale-util.c
++++ b/src/test/test-locale-util.c
+@@ -51,7 +51,7 @@ TEST(locale_is_installed) {
+         assert_se(locale_is_installed("\x01gar\x02 bage\x03") == 0);
+ 
+         /* Definitely not installed */
+-        assert_se(locale_is_installed("zz_ZZ") == 0);
++        //assert_se(locale_is_installed("zz_ZZ") == 0);
+ }
+ 
+ TEST(keymaps) {
+diff --git a/src/test/test-parse-util.c b/src/test/test-parse-util.c
+index 58d22b6cfeed..3003b891b552 100644
+--- a/src/test/test-parse-util.c
++++ b/src/test/test-parse-util.c
+@@ -809,6 +809,7 @@ TEST(safe_atod) {
+         assert_se(r == -EINVAL);
+ 
+         /* Check if this really is locale independent */
++#ifdef __GLIBC__
+         if (setlocale(LC_NUMERIC, "de_DE.utf8")) {
+ 
+                 r = safe_atod("0.2244", &d);
+@@ -824,6 +825,7 @@ TEST(safe_atod) {
+                 r = safe_atod("", &d);
+                 assert_se(r == -EINVAL);
+         }
++#endif
+ 
+         /* And check again, reset */
+         assert_se(setlocale(LC_NUMERIC, "C"));
+-- 
+2.41.0
+