slurm-spank-x11: add backward compatibility patch

pkgs/by-name/sl/slurm-spank-x11/backward-compat.patch

@@ -0,0 +1,15 @@
+diff --git a/slurm-spank-x11-plug.c b/slurm-spank-x11-plug.c
+index bef6c14..feaf041 100644
+--- a/slurm-spank-x11-plug.c
++++ b/slurm-spank-x11-plug.c
+@@ -36,6 +36,10 @@
+ 
+ #include <stdint.h>
+ 
++#ifndef SLURM_BACKWARD_COMPAT
++#define SLURM_BACKWARD_COMPAT 1
++#endif
++
+ #include <slurm/slurm.h>
+ #include <slurm/spank.h>
+ 

pkgs/by-name/sl/slurm-spank-x11/package.nix

@@ -15,7 +15,10 @@ stdenv.mkDerivation (finalAttrs: {
     sha256 = "1dmsr7whxcxwnlvl1x4s3bqr5cr6q5ssb28vqi67w5hj4sshisry";
   };
 
-  patches = [ ./hostlist.patch ];
+  patches = [
+    ./hostlist.patch
+    ./backward-compat.patch
+  ];
 
   # Required for build with gcc-14
   env.NIX_CFLAGS_COMPILE = "-Wno-error=implicit-function-declaration";