llvm: Don't depend on binutils for ghcjs platform

This dependency was introduced by unconditionally enabled
enableGoldPlugin option, which was enabled only if libbfd explicitly
supports plugin api prior to llvm-16. In llvm-17+ it was enabled
unconditionally (unless overriden explicitly), which introduces
dependency on binutils for target platform and breaks build for
platforms that are not supported by binutils (such as ghcjs).

pkgs/development/compilers/llvm/17/llvm/default.nix

@@ -8,7 +8,7 @@
 , python3
 , python3Packages
 , libffi
-, enableGoldPlugin ? true
+, enableGoldPlugin ? libbfd.hasPluginAPI
 , libbfd
 , libpfm
 , libxml2

pkgs/development/compilers/llvm/18/llvm/default.nix

@@ -8,7 +8,7 @@
 , python3
 , python3Packages
 , libffi
-, enableGoldPlugin ? true
+, enableGoldPlugin ? libbfd.hasPluginAPI
 , libbfd
 , libpfm
 , libxml2

pkgs/development/compilers/llvm/git/llvm/default.nix

@@ -8,7 +8,7 @@
 , python3
 , python3Packages
 , libffi
-, enableGoldPlugin ? true
+, enableGoldPlugin ? libbfd.hasPluginAPI
 , libbfd
 , libpfm
 , libxml2