settings: allow scroll in LED settings's color dialog

This is useful in mdpi devices and landscape mode, when the current layout rebased the dialog height

Change-Id: I7f9cd936076d3409e78a8f6b9a24b180a36a2bc8
Signed-off-by: Jorge Ruesga <jorge@ruesga.com>
Merge branch 'cm-11.0' of https://github.com/CyanogenMod/android_packages_apps_Settings into android-4.4_new