fort_dyn_array: Use value constructor instead of raw-buffer manipulation.

fort_dyn_array: Use value constructor instead of raw-buffer manipulation.

Instead of pre-computing indices into a fortran array re-use
the value_* interfaces to subscript a fortran array.
The benefit of using the new interface is that it takes care of
dynamic types and resolve them when needed.
This fixes issues when printing structures with dynamic arrays from toplevel.

Before:
(gdb) p twov
$1 = ( (( ( 6352320, 0, -66, -1, 267) ( 343476, 1, -15, 1, 0) ( 5, 0, 5, 0, 1) ...

After:
(gdb) p twov
$1 = ( (( ( 1, 1, 1, 1, 1) ( 1, 1, 321, 1, 1) ( 1, 1, 1, 1, 1) ...

2016-04-26  Sanimir Agovic  <sanimir.agovic@intel.com>
            Keven Boell  <keven.boell@intel.com>
            Bernhard Heckel  <bernhard.heckel@intel.com>

gdb/Changelog:
	* f-valprint.c (f77_create_arrayprint_offset_tbl): Remove
	function.
	(F77_DIM_SIZE, F77_DIM_OFFSET): Remove macro.
	(f77_print_array_1): Use value_subscript to subscript a
	value array.
	(f77_print_array): Remove call to f77_create_arrayprint_offset_tbl.
	(f_val_print): Use value_field to construct a field value.

gdb/testsuite/Changelog:
	* vla-type.exp: Print structure from toplevel.