Fix the flag used to force linking when we are making a shared library

This is a correction to the patch:
* When linking a shared library with --make, always do the link step
which used the wrong flag in making the decision. It used -dynamic
whereas the correct flag is -shared.

compiler/main/GHC.hs

@@ -888,7 +888,7 @@ load2 how_much mod_graph = do
 	      let 
 	 	main_mod = mainModIs dflags
 		a_root_is_Main = any ((==main_mod).ms_mod) mod_graph
-		do_linking = a_root_is_Main || no_hs_main || not StaticFlags.opt_Static
+		do_linking = a_root_is_Main || no_hs_main || ghcLink dflags == LinkDynLib
 
 	      when (ghcLink dflags == LinkBinary 
                     && isJust ofile && not do_linking) $