gendwarfksyms: Expand array_type

gendwarfksyms: Expand array_type

Add support for expanding DW_TAG_array_type, and the subrange type
indicating array size.

Example source code:

  const char *s[34];

Output with --dump-dies:

  variable array_type[34] {
    pointer_type {
      const_type {
        base_type char byte_size(1) encoding(6)
      }
    } byte_size(8)
  }

Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Petr Pavlu <petr.pavlu@suse.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>