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

AICPfy:
PS2 - Fix FC

Change-Id: I7f9cd936076d3409e78a8f6b9a24b180a36a2bc8
Signed-off-by: Jorge Ruesga <jorge@ruesga.com>