DynFlags: remove unused sPgm_sysman (#8689)

Something about a long deleted 'system manager' for the 'parallel
system'.

Also remove confusing comment in SysTools, that supposedly referred to
sPgm_sysman. See commit 16d5d1c7.

compiler/main/DynFlags.hs

@@ -71,7 +71,7 @@ module DynFlags (
         versionedAppDir,
         extraGccViaCFlags, systemPackageConfig,
         pgm_L, pgm_P, pgm_F, pgm_c, pgm_s, pgm_a, pgm_l, pgm_dll, pgm_T,
-        pgm_sysman, pgm_windres, pgm_libtool, pgm_lo, pgm_lc,
+        pgm_windres, pgm_libtool, pgm_lo, pgm_lc,
         opt_L, opt_P, opt_F, opt_c, opt_a, opt_l,
         opt_windres, opt_lo, opt_lc,
 
@@ -974,7 +974,6 @@ data Settings = Settings {
   sPgm_l                 :: (String,[Option]),
   sPgm_dll               :: (String,[Option]),
   sPgm_T                 :: String,
-  sPgm_sysman            :: String,
   sPgm_windres           :: String,
   sPgm_libtool           :: String,
   sPgm_lo                :: (String,[Option]), -- LLVM: opt llvm optimiser
@@ -1031,8 +1030,6 @@ pgm_dll               :: DynFlags -> (String,[Option])
 pgm_dll dflags = sPgm_dll (settings dflags)
 pgm_T                 :: DynFlags -> String
 pgm_T dflags = sPgm_T (settings dflags)
-pgm_sysman            :: DynFlags -> String
-pgm_sysman dflags = sPgm_sysman (settings dflags)
 pgm_windres           :: DynFlags -> String
 pgm_windres dflags = sPgm_windres (settings dflags)
 pgm_libtool           :: DynFlags -> String

compiler/main/SysTools.hs

@@ -343,13 +343,10 @@ initSysTools mbMinusB
                     sPgm_l   = (ld_prog, ld_args),
                     sPgm_dll = (mkdll_prog,mkdll_args),
                     sPgm_T   = touch_path,
-                    sPgm_sysman  = top_dir ++ "/ghc/rts/parallel/SysMan",
                     sPgm_windres = windres_path,
                     sPgm_libtool = libtool_path,
                     sPgm_lo  = (lo_prog,[]),
                     sPgm_lc  = (lc_prog,[]),
-                    -- Hans: this isn't right in general, but you can
-                    -- elaborate it in the same way as the others
                     sOpt_L       = [],
                     sOpt_P       = [],
                     sOpt_F       = [],