nvidia-x11: Fix the library-only build

Also, introduce a function ‘versionAtLeast’ which is probably more
natural than ‘versionOlder’.

pkgs/lib/strings.nix

@@ -163,6 +163,10 @@ rec {
   versionOlder = v1: v2: builtins.compareVersions v2 v1 == 1;
 
 
+  # Return true iff string v1 denotes a version equal to or newer than v2.
+  versionAtLeast = v1: v2: !versionOlder v1 v2;
+
+
   # Get the version of the specified derivation, as specified in its
   # ‘name’ attribute.
   getVersion = drv: (builtins.parseDrvName drv.name).version;

pkgs/os-specific/linux/nvidia-x11/default.nix

@@ -25,7 +25,7 @@ stdenv.mkDerivation {
 
   patches =
     [ ./version-test.patch ]
-    ++ optional (!versionOlder kernelDev.version "3.10") kernel310patch;
+    ++ optional (!libsOnly && versionAtLeast kernelDev.version "3.10") kernel310patch;
 
   src =
     if stdenv.system == "i686-linux" then