haskell.compiler.*: use symlinks from bintool wrapper if possible

Ideally we don't want to use bintools.bintools and also not really
encode knowledge of what is wrapped and what not in our GHC derivation.
Unfortunately, not all tools are part of the wrapper derivation as well.
This should be gradually improved (e.g. in the case of the darwin tools
and strip).

pkgs/development/compilers/ghc/8.10.7.nix

@@ -158,12 +158,12 @@ let
       tools = {
         "cc" = cc;
         "c++" = cc;
-        as = cc.bintools.bintools;
+        as = cc.bintools;
 
-        ar = cc.bintools.bintools;
-        ranlib = cc.bintools.bintools;
-        nm = cc.bintools.bintools;
-        readelf = cc.bintools.bintools;
+        ar = cc.bintools;
+        ranlib = cc.bintools;
+        nm = cc.bintools;
+        readelf = cc.bintools;
         objdump = cc.bintools;
 
         ld = cc.bintools;

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

@@ -306,12 +306,12 @@ let
       tools = {
         "cc" = cc;
         "c++" = cc;
-        as = cc.bintools.bintools;
+        as = cc.bintools;
 
-        ar = cc.bintools.bintools;
-        ranlib = cc.bintools.bintools;
-        nm = cc.bintools.bintools;
-        readelf = cc.bintools.bintools;
+        ar = cc.bintools;
+        ranlib = cc.bintools;
+        nm = cc.bintools;
+        readelf = cc.bintools;
         objdump = cc.bintools;
 
         ld = cc.bintools;

pkgs/development/compilers/ghc/common-make-native-bignum.nix

@@ -161,12 +161,12 @@ let
       tools = {
         "cc" = cc;
         "c++" = cc;
-        as = cc.bintools.bintools;
+        as = cc.bintools;
 
-        ar = cc.bintools.bintools;
-        ranlib = cc.bintools.bintools;
-        nm = cc.bintools.bintools;
-        readelf = cc.bintools.bintools;
+        ar = cc.bintools;
+        ranlib = cc.bintools;
+        nm = cc.bintools;
+        readelf = cc.bintools;
         objdump = cc.bintools;
 
         ld = cc.bintools;