fix spinner height and y to resolve broken layout chain

everything lays out relative to the spinner/logo, when changing to in-cpu
rotation the spinner code was not correctly updated to retain working
y and height calculations after changes to internal data structures.
this resulted in all objects layed out relative to the spinner to not
be drawn as their position was NaN.

plymouth could really benefit from openqa tests :/

BUG: 365169
FIXED-IN: 5.7.1