[Ada] do not print arrays as array pointers

This patch enhances the debugger to distinguish between fat pointers
that represent either: array types, or array access types.  In the latter
case, the object/type is encoded as a typedef type pointing to the fat
pointer.

The first part of the change is to adjust ada_check_typedef to avoid
stripping the typedef layer when it points to a fat pointer.  The rest
of the patch is adjustments required in various places to deal with
the fact that the type is uses might now be a typedef.

gdb/ChangeLog:

        * ada-lang.h (ada_coerce_to_simple_array): Add declaration.
        * ada-lang.c (ada_typedef_target_type): New function.
        (desc_base_type): Add handling of fat pointer typedefs.
        (ada_coerce_to_simple_array): Make non-static.
        (decode_packed_array_bitsize): Add handling of fat pointer typedefs.
        Add assertion.
        (ada_template_to_fixed_record_type_1, ada_to_fixed_type)
        (ada_check_typedef): Add handling of fat pointer typedefs.
        (ada_evaluate_subexp) [OP_FUNCALL]: Likewise.
        * ada-typeprint.c (ada_print_type): Add handling of fat pointer
        typedefs.
        * ada-valprint.c (ada_val_print_1): Convert fat pointers that are not
        array accesses to simple arrays rather than simple array pointers.
        (ada_value_print): In the case of array descriptors, do not print
        the value type description unless it is an array access.

gdb/testsuite/ChangeLog:

        * gdb.ada/lang_switch.exp: Correct expected parameter value.

gdb/doc/ChangeLog:

        * gdb.texinfo (Ada Glitches): Remove paragraph describing the
        occasional case where the debugger prints an array address
        instead of the array itself.

gdb/ada-lang.h

@@ -197,6 +197,8 @@ struct type *ada_type_of_array (struct value *, int);
 
 extern struct value *ada_coerce_to_simple_array_ptr (struct value *);
 
+struct value *ada_coerce_to_simple_array (struct value *);
+
 extern int ada_is_simple_array_type (struct type *);
 
 extern int ada_is_array_descriptor_type (struct type *);