Remove coolbits script (document the nvidia-xconfig command to use instead)

extra/88-gsr-coolbits.conf

@@ -1,5 +0,0 @@
-Section "Device"
-    Identifier     "Device0"
-    Driver         "nvidia"
-    Option         "Coolbits" "12"
-EndSection

extra/install_coolbits.sh

@@ -1,10 +0,0 @@
-#!/bin/sh
-
-script_dir=$(dirname "$0")
-cd "$script_dir"
-
-[ $(id -u) -ne 0 ] && echo "You need root privileges to run the install script" && exit 1
-
-for xorg_conf_d in "/etc/X11/xorg.conf.d" "/usr/share/X11/xorg.conf.d" "/usr/lib/X11/xorg.conf.d"; do
-    [ -d "$xorg_conf_d" ] && install -Dm644 "88-gsr-coolbits.conf" "$xorg_conf_d/88-gsr-coolbits.conf" && exit 0
-done