scryer-prolog: Remove gmp, libmpc and mprf

Since 0.9.3 Scryer Prolog uses the Rust crate dashu to do
arbitrary precision arithmetic, and so doesn't need these
dependencies anymore.

pkgs/development/compilers/scryer-prolog/default.nix

@@ -3,9 +3,6 @@
 , fetchFromGitHub
 , pkg-config
 , openssl
-, gmp
-, libmpc
-, mpfr
 , stdenv
 , darwin
 }:
@@ -25,7 +22,7 @@ rustPlatform.buildRustPackage rec {
 
   nativeBuildInputs = [ pkg-config ];
 
-  buildInputs = [ openssl gmp libmpc mpfr ]
+  buildInputs = [ openssl ]
                 ++ lib.optionals stdenv.isDarwin [
                   darwin.apple_sdk.frameworks.SystemConfiguration
                 ];