gmid: fix cross-compilation

pkgs/servers/gemini/gmid/default.nix

···
-{ lib, stdenv, fetchFromGitHub, bison, libressl, libevent }:
+{ lib, stdenv, fetchFromGitHub, fetchpatch, bison, libressl, libevent }:
 
 stdenv.mkDerivation rec {
   pname = "gmid";
···
     rev = version;
     sha256 = "sha256-BBd0AL5jRRslxzDnxcTZRR+8J5D23NAQ7mp9K+leXAQ=";
   };
+
+  patches = [
+    # Fix cross-compilation
+    (fetchpatch {
+      url = "https://github.com/omar-polo/gmid/commit/eb77afa8d308a2f4f422df2ff19f023b5b2cc591.patch";
+      sha256 = "sha256-rTTZUpfXOg7X0Ad0Y9evyU7k+aVYpJ0t9SEkNA/sSdk=";
+    })
+  ];
 
   nativeBuildInputs = [ bison ];