ada: TSS finalize address subprogram generation for constrained...

ada: TSS finalize address subprogram generation for constrained...

...subtypes of unconstrained synchronized private extensions should take
care to designate the corresponding record of the underlying concurrent
type.

When generating TSS finalize address subprograms for class-wide types of
constrained root types, it follows the parent chain looking for the
first "non-constrained" type. It is possible that such a type is a
private extension with the “synchronized” keyword, in which case the
underlying type is a concurrent type. When that happens, the designated
type of the finalize address subprogram should be the corresponding
record’s class-wide-type.

gcc/ada/ChangeLog:
	* exp_ch3.adb (Expand_Freeze_Class_Wide_Type): Expanded comments
	explaining why TSS Finalize_Address is not generated for
	concurrent class-wide types.
	* exp_ch7.adb (Make_Finalize_Address_Stmts): Handle cases where the
	underlying non-constrained parent type is a concurrent type, and
	adjust the designated type to be the corresponding record’s
	class-wide type.

gcc/testsuite/ChangeLog:

	* gnat.dg/sync_tag_finalize.adb: New test.

Signed-off-by: Richard Wai <richard@annexi-strayline.com>