pyramid: Add sysfs switch for basic color control

 The sysfs switch allows switching between the old color configuration
 and the new one. Sysfs switch is located at
 /sys/module/mdp/parameters/mdp_gamma_cooler_colors. The cooler color
 profile is disabled by default. The sysfs switch can be written to
 on-the-go; turn the screen off and on to apply the new color profile.

 Signed-off-by: Sultanxda <sultanxda@gmail.com>