gerbil: 0.15.1 -> 0.16

Now that v0.16 was released at last, make the configurePhase and instalPhase
the same again for default and unstable.

pkgs/development/compilers/gerbil/unstable.nix

@@ -1,4 +1,4 @@
-{ callPackage, fetchFromGitHub, gambit-unstable, gambit-support, coreutils, bash }:
+{ callPackage, fetchFromGitHub, gambit-unstable, gambit-support }:
 
 callPackage ./build.nix rec {
   version = "unstable-2020-05-17";
@@ -12,23 +12,4 @@ callPackage ./build.nix rec {
   inherit gambit-support;
   gambit = gambit-unstable;
   gambit-params = gambit-support.unstable-params;
-  configurePhase = ''
-    (cd src && ./configure \
-      --prefix=$out/gerbil \
-      --with-gambit=${gambit}/gambit \
-      --enable-libxml \
-      --enable-libyaml \
-      --enable-zlib \
-      --enable-sqlite \
-      --enable-mysql \
-      --enable-lmdb \
-      --enable-leveldb)
-  '';
-  installPhase = ''
-    runHook preInstall
-    mkdir -p $out/gerbil $out/bin
-    (cd src; ./install)
-    (cd $out/bin ; ln -s ../gerbil/bin/* .)
-    runHook postInstall
-  '';
 }