nixd: link LLVM's support component statically

nixd only uses LLVM's Support/ADT utilities, but linking the monolithic
libLLVM dylib pulled the entire ~550 MiB LLVM lib output into the
runtime closure. 2.9.2 adds a meson option to link the static "support"
component instead; closure goes from 702 MiB to 158 MiB

pkgs/development/tools/language-servers/nixd/default.nix

@@ -18,6 +18,8 @@
   pkg-config,
   testers,
   python3,
+  libxml2,
+  zlib,
 }:
 
 let
@@ -145,10 +147,16 @@ in
         llvmPackages.llvm
         gtest
         boost
+        libxml2
+        zlib
       ];
 
       nativeBuildInputs = common.nativeBuildInputs ++ [ cmake ];
 
+      mesonFlags = [ (lib.mesonBool "llvm_static" true) ];
+
+      disallowedRequisites = [ (lib.getLib llvmPackages.llvm) ];
+
       # See https://github.com/nix-community/nixd/issues/519
       doCheck = false;