gdb/fortran: Show the type for non allocated / associated types

gdb/fortran: Show the type for non allocated / associated types

Show the type of not-allocated and/or not-associated types.  For array
types and pointer to array types we are going to print the number of
ranks.

Consider this Fortran program:

  program test
    integer, allocatable :: vla (:)
    logical l
    allocate (vla(5:12))
    l = allocated (vla)
  end program test

And this GDB session with current HEAD:

  (gdb) start
  ...
  2	  integer, allocatable :: vla (:)
  (gdb) n
  4	  allocate (vla(5:12))
  (gdb) ptype vla
  type = <not allocated>
  (gdb) p vla
  $1 = <not allocated>
  (gdb)

And the same session with this patch applied:

  (gdb) start
  ...
  2	  integer, allocatable :: vla (:)
  (gdb) n
  4	  allocate (vla(5:12))
  (gdb) ptype vla
  type = integer(kind=4), allocatable (:)
  (gdb) p vla
  $1 = <not allocated>
  (gdb)

The type of 'vla' is now printed correctly, while the value itself
still shows as '<not allocated>'.  How GDB prints the type of
associated pointers has changed in a similar way.

gdb/ChangeLog:

	* f-typeprint.c (f_print_type): Don't return early for not
	associated or not allocated types.
	(f_type_print_varspec_suffix): Add print_rank parameter and print
	ranks of array types in case they dangling.
	(f_type_print_base): Add print_rank parameter.

gdb/testsuite/ChangeLog:

	* gdb.fortran/pointers.f90: New file.
	* gdb.fortran/print_type.exp: New file.
	* gdb.fortran/vla-ptype.exp: Adapt expected results.
	* gdb.fortran/vla-type.exp: Likewise.
	* gdb.fortran/vla-value.exp: Likewise.
	* gdb.mi/mi-vla-fortran.exp: Likewise.