gdb/dwarf: rename comp_unit_die to top_level_die The name "comp_unit_die" is a bit misleading, because it can also represent a type unit (DW_TAG_type_unit). I think that "top_level_die" is clear. Change-Id: Ibaac99897f0ac7499f0f82caeed3385e1e6ee870 Approved-By: Tom Tromey <tom@tromey.com>