Revert "Change TLP charge thresholds"

This reverts commit 76f681355c.

This setting is opinionated and should be left to the user.
See: https://github.com/NixOS/nixos-hardware/pull/154#issuecomment-617181517

lenovo/thinkpad/x230/default.nix

@@ -16,10 +16,4 @@
   services.xserver.deviceSection = lib.mkDefault ''
     Option "TearFree" "true"
   '';
-
-  services.tlp.extraConfig = lib.mkDefault ''
-    START_CHARGE_THRESH_BAT0=67
-    STOP_CHARGE_THRESH_BAT0=100
-  '';
-
 }