mk-component-set: wrap gcc-ld/ld.lld instead of multicall rust-lld

Other flavor dispatchers may use different CLI (eg. MSVC 'link' style)
and our wrapper cannot handle all of them. They are usually used for
exotic targets like UEFI or WASM ones, where Nix libraries cannot be
used without manual configuration anyway.

Author: oxalica

ld-wrapper.sh

@@ -124,18 +124,19 @@ let
           chmod +x "$dst"
         }
 
-        dsts=( "$out"/lib/rustlib/*/bin/rust-lld )
+        dsts=( "$out"/lib/rustlib/*/bin/gcc-ld/ld.lld )
         if [[ ''${#dsts} -ne 0 ]]; then
-          ls -lah $out
           mkdir -p $out/nix-support
           substituteAll ${path + "/pkgs/build-support/wrapper-common/utils.bash"} $out/nix-support/utils.bash
           substituteAll ${path + "/pkgs/build-support/bintools-wrapper/add-flags.sh"} $out/nix-support/add-flags.sh
           substituteAll ${path + "/pkgs/build-support/bintools-wrapper/add-hardening.sh"} $out/nix-support/add-hardening.sh
 
           for dst in "''${dsts[@]}"; do
-            unwrapped="$(dirname "$dst")/.rust-lld-unwrapped"
+            # The ld.lld is path/name sensitive because itself is a wrapper. Keep its original name.
+            unwrapped="$(dirname "$dst")-unwrapped/ld.lld"
+            mkdir -p "$(dirname "$unwrapped")"
             mv "$dst" "$unwrapped"
-            wrap "$dst" ${./ld-wrapper.sh} "$unwrapped"
+            wrap "$dst" ${path + "/pkgs/build-support/bintools-wrapper/ld-wrapper.sh"} "$unwrapped"
           done
         fi
       '';