Merge pull request #122857 from dguibert/dg/perf_kernel_3_12

perf: define only if kernel version > 3.12

pkgs/top-level/all-packages.nix

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     oci-seccomp-bpf-hook = if lib.versionAtLeast kernel.version "5.4" then callPackage ../os-specific/linux/oci-seccomp-bpf-hook { } else null;
 
-    perf = callPackage ../os-specific/linux/kernel/perf.nix { };
+    perf = if lib.versionAtLeast kernel.version "3.12" then callPackage ../os-specific/linux/kernel/perf.nix { } else null;
 
     phc-intel = if lib.versionAtLeast kernel.version "4.10" then callPackage ../os-specific/linux/phc-intel { } else null;