bbswitch: add libelf to buildInputs

Signed-off-by: Christoph Hrdinka <c.github@hrdinka.at>

pkgs/os-specific/linux/bbswitch/default.nix

@@ -1,4 +1,4 @@
-{ stdenv, fetchurl, fetchpatch, kernel }:
+{ stdenv, fetchurl, fetchpatch, kernel, libelf }:
 
 let
   baseName = "bbswitch";
@@ -20,6 +20,8 @@ stdenv.mkDerivation {
     sha256 = "1lbr6pyyby4k9rn2ry5qc38kc738d0442jhhq57vmdjb6hxjya7m";
   }) ];
 
+  buildInputs = [ libelf ];
+
   hardeningDisable = [ "pic" ];
 
   preBuild = ''