haskell.compiler.ghcHEAD: drop malformed/redundant hadrian setting

`*.*.rts.*.opts` is actually copied from the migration GHC blog post,
but does not, actually, parse: The format is
`<stage>.<package>.<program>.<filetype>.<setting>`, so it would need to
be `*.rts.ghc.opts`. This is already achieved by the broader rule on the
next line.

pkgs/development/compilers/ghc/common-hadrian.nix

@@ -182,7 +182,6 @@ let
     # be needed for TemplateHaskell. This solution was described in
     # https://www.tweag.io/blog/2020-09-30-bazel-static-haskell
     lib.optionals enableRelocatedStaticLibs [
-      "*.*.rts.*.opts += -fPIC -fexternal-dynamic-refs"
       "*.*.ghc.*.opts += -fPIC -fexternal-dynamic-refs"
     ]
     ++ lib.optionals targetPlatform.useAndroidPrebuilt [