Benchmarks: Remove base-compat dependency

The `plated` benchmark suite previously had a dependency on `base-compat`,
which was introduced in #909 for compatibility with pre-7.10 versions of GHC.
In #977, however, the minimum version of GHC was raised to 8.0, which means
that there is no longer any reason for these benchmarks to depend on
`base-compat`. This patch removes the dependency.

benchmarks/plated.hs

@@ -4,13 +4,6 @@
 {-# OPTIONS_GHC -funbox-strict-fields #-}
 module Main (main) where
 
-#ifndef MIN_VERSION_base
-#define MIN_VERSION_base(x,y,z) 1
-#endif
-
-import Prelude ()
-import Prelude.Compat
-
 import           Control.Lens
 import           Control.DeepSeq
 import           Criterion.Main

lens.cabal

@@ -410,7 +410,6 @@ benchmark plated
   default-language: Haskell2010
   build-depends:
     base,
-    base-compat >=0.11.0 && <0.15,
     comonad,
     criterion,
     deepseq,