Fix comment to explain that this is host platform info

Because cabal2nix and haskell.nix work at all, I'm confident the new
comment is also more correct as to how this function is used in
practice.

Author: Ericson2314

Cabal/src/Distribution/PackageDescription/Configuration.hs

@@ -169,8 +169,8 @@ resolveWithFlags ::
      [(FlagName,[Bool])]
         -- ^ Domain for each flag name, will be tested in order.
   -> ComponentRequestedSpec
-  -> OS      -- ^ OS as returned by Distribution.System.buildOS
-  -> Arch    -- ^ Arch as returned by Distribution.System.buildArch
+  -> OS      -- ^ OS where the installed artifacts will run (host OS)
+  -> Arch    -- ^ Arch where the installed artifacts will run (host Arch)
   -> CompilerInfo  -- ^ Compiler information
   -> [PackageVersionConstraint]  -- ^ Additional constraints
   -> [CondTree ConfVar [Dependency] PDTagged]