koboldcpp: fix CUDA_DOCKER_ARCH make flag

- Previously, the value was "assembled" using additional logic, but
  when switching to a different method, an oversight was made, and
  `sm_` was forgotten to be removed

pkgs/by-name/ko/koboldcpp/package.nix

@@ -129,8 +129,7 @@ effectiveStdenv.mkDerivation (finalAttrs: {
     (makeBool "LLAMA_CLBLAST" clblastSupport)
     (makeBool "LLAMA_VULKAN" vulkanSupport)
     (makeBool "LLAMA_METAL" metalSupport)
-    (lib.optionals cublasSupport "CUDA_DOCKER_ARCH=sm_${builtins.head cudaArches}")
-  ];
+  ] ++ lib.optionals cublasSupport [ "CUDA_DOCKER_ARCH=${builtins.head cudaArches}" ];
 
   installPhase = ''
     runHook preInstall