* freeze.adb (Freeze_Record_Type): Move choice checking to
Analyze_Freeze_Entity (Freeze_Record_Type): Make sure all choices
are properly frozen
* sem_case.adb (Check_Choices): Remove misguided attempt to
freeze choices (this is now done in Freeze_Record_Type where
it belongs).
(Check_Choices): Remove some analyze/resolve calls
that are redundant since they are done in Analyze_Choices.
* sem_ch13.adb (Analyze_Freeze_Entity): Do the error
checking for choices in variant records here (moved here from
Freeze.Freeze_Record_Type)