Fixes issues when camera center would not change altitude if exaggeration changed and that camera could appear under terrain.

Similar to #11461, the customer was affected (https://github.com/mapbox/mapbox-maps-android-internal/issues/850) by camera moved underground when animating exaggeration, increasing it from 0 in high altitude areas. In such an use case, we didn't adjust center and camera MSL altitude with exaggeration change.

Extended usage of Transform._centerAltitudeValid to renamed _centerAltitudeValidForExaggeration: while data is not available, _centerAltitudeValidForExaggeration is 0. As soon as center elevation is available, new value for _centerAltitudeValidForExaggeration would trigger camera altitude adjustment in updateElevation.

Added exaggeration change on zoom (issue  #11044 is still open) and pitch (bug #11589) to fog demo.

Fixes: #11589