hadrian: Correct generation of hsc2hs wrapper

If you inspect the inside of a wrapper script for hsc2hs you will see
that the cflag and lflag values are concatenated incorrectly.

```
HSC2HS_EXTRA="--cflag=-U__i686--lflag=-fuse-ld=gold"
```

It should instead be

```
HSC2HS_EXTRA="--cflag=-U__i686 --lflag=-fuse-ld=gold"
```

Fixes #21221

hadrian/src/Rules/BinaryDist.hs

@@ -417,7 +417,7 @@ hsc2hsWrapper = do
   ldFlags <- map ("--lflag=" <>) <$> settingList (ConfGccLinkerArgs Stage1)
   wrapper <- drop 4 . lines <$> liftIO (readFile "utils/hsc2hs/hsc2hs.wrapper")
   return $ unlines
-    ( "HSC2HS_EXTRA=\"" <> unwords ccArgs <> unwords ldFlags <> "\""
+    ( "HSC2HS_EXTRA=\"" <> unwords (ccArgs ++ ldFlags) <> "\""
     : "tflag=\"--template=$libdir/template-hsc.h\""
     : "Iflag=\"-I$includedir/\""
     : wrapper )