LineageParts: Fix loading default colors for non-RGB lights

* Commit Iab1dcad048de838bb9015c62a4171b002141f09a
  moved default color overlay loading from resetColors to
  mDefaultLowColor/mDefaultMediumColor/mDefaultFullColor
  but those were only set for RGB lights, so we always defaulted
  to no color on non-RGB lights when resetColors was run.
* Load default colors for non-RGB lights as well and do some minor cleanup

Change-Id: I578a895fe23b65ee50436091c4f31907fba9961d