refactor(cabal-install-solver)!: remove dead code

principalPP and setupPP seem to have gone unused since
8194fab

Author: andreabedini

cabal-install-solver/src/Distribution/Solver/Modular/Package.hs

@@ -11,8 +11,6 @@ module Distribution.Solver.Modular.Package
   , QPV
   , instI
   , makeIndependent
-  , primaryPP
-  , setupPP
   , showI
   , showPI
   , unPN
@@ -77,28 +75,6 @@ instI :: I -> Bool
 instI (I _ (Inst _)) = True
 instI _              = False
 
--- | Is the package in the primary group of packages.  This is used to
--- determine (1) if we should try to establish stanza preferences
--- for this goal, and (2) whether or not a user specified @--constraint@
--- should apply to this dependency (grep 'primaryPP' to see the
--- use sites).  In particular this does not include packages pulled in
--- as setup deps.
---
-primaryPP :: PackagePath -> Bool
-primaryPP (PackagePath _ns q) = go q
-  where
-    go QualToplevel    = True
-    go (QualSetup _)   = False
-    go (QualExe _ _)   = False
-
--- | Is the package a dependency of a setup script.  This is used to
--- establish whether or not certain constraints should apply to this
--- dependency (grep 'setupPP' to see the use sites).
---
-setupPP :: PackagePath -> Bool
-setupPP (PackagePath _ns (QualSetup _)) = True
-setupPP (PackagePath _ns _)         = False
-
 -- | Qualify a target package with its own name so that its dependencies are not
 -- required to be consistent with other targets.
 makeIndependent :: PN -> QPN