gnuradio3_8: fix build by using volk_2

pkgs/top-level/all-packages.nix

@@ -30305,6 +30305,7 @@ with pkgs;
     unwrapped = callPackage ../applications/radio/gnuradio/3.8.nix ({
       inherit (darwin.apple_sdk.frameworks) CoreAudio;
       python = python311;
+      volk = volk_2;
     } // lib.optionalAttrs stdenv.isLinux {
       stdenv = pkgs.stdenvAdapters.useLibsFrom stdenv pkgs.gcc12Stdenv;
     });
@@ -30315,7 +30316,7 @@ with pkgs;
   gnuradio3_8Minimal = gnuradio3_8.override {
     doWrap = false;
     unwrapped = gnuradio3_8.unwrapped.override {
-      volk = volk.override {
+      volk = volk_2.override {
         enableModTool = false;
       };
       uhd = uhdMinimal;