librist: fix build for musl

(cherry picked from commit 01fe6fb38d)

pkgs/by-name/li/librist/musl.patch

@@ -0,0 +1,16 @@
+diff --git a/test/rist/unit/srp_examples.c b/test/rist/unit/srp_examples.c
+index 1c5193d..6f835b5 100644
+--- a/test/rist/unit/srp_examples.c
++++ b/test/rist/unit/srp_examples.c
+@@ -16,6 +16,11 @@
+ #define DEBUG_USE_EXAMPLE_CONSTANTS 1
+ 
+ #if HAVE_MBEDTLS
++// musl's sched.h includes a prototype for calloc, so we need to make
++// sure it's already been included before we redefine it to something
++// that won't expand to a valid prototype.
++#include <sched.h>
++
+ #define malloc(size) _test_malloc(size, __FILE__, __LINE__)
+ #define calloc(num, size) _test_calloc(num, size, __FILE__, __LINE__)
+ #define free(obj) _test_free(obj, __FILE__, __LINE__)

pkgs/by-name/li/librist/package.nix

@@ -24,6 +24,8 @@ stdenv.mkDerivation rec {
   patches = [
     # https://github.com/NixOS/nixpkgs/pull/257020
     ./darwin.patch
+    # https://code.videolan.org/rist/librist/-/merge_requests/257
+    ./musl.patch
   ];
 
   nativeBuildInputs = [