Allow led brightness and color to be controlled separately

Having separate control for led brightness allows tuning of ongoing
breathing pattern without resetting the step counter which
caused visible flickering.

[hybris.so] Allow led brightness and color to be controlled separately. Contributes to JB#19788
Unify indentation
Clarify why breathing is a special case from led control point of view
Clarify why mce_hybris_indicator_set_brightness() always returns true
Merge pull request #11 from spiiroin/led_brightness

Allow led brightness and color to be controlled separately