[musl] explicitly build ghc-iserv-prof (#1898)

Author: angerman

compiler/ghc/default.nix

@@ -684,6 +684,10 @@ stdenv.mkDerivation (rec {
     ${hadrian}/bin/hadrian ${hadrianArgs} stage1:lib:terminfo
   '' + lib.optionalString (installStage1 && !haskell-nix.haskellLib.isCrossTarget) ''
     ${hadrian}/bin/hadrian ${hadrianArgs} stage2:exe:iserv
+    # I don't seem to be able to build _build/stage1/lib/bin/ghc-iserv-prof
+    # by asking hadrian for this. The issue is likely that the profiling way
+    # is probably missing from hadrian m(
+    ${hadrian}/bin/hadrian ${hadrianArgs} _build/stage1/lib/bin/ghc-iserv-prof
     pushd _build/stage1/bin
     for exe in *; do
       mv $exe ${targetPrefix}$exe