Introduce ada_value_print_array

Introduce ada_value_print_array

This adds ada_value_print_array, a value-based analogue of
ada_val_print_array.  It also removes some unused parameters from a
couple of helper functions.

gdb/ChangeLog
2020-03-13  Tom Tromey  <tom@tromey.com>

	* ada-valprint.c (val_print_packed_array_elements): Remove
	bitoffset and val parameters.  Call common_val_print.
	(ada_val_print_string): Remove offset, address, and original_value
	parameters.
	(ada_val_print_array): Update.
	(ada_value_print_array): New function.
	(ada_value_print_1): Call it.