dwarf-reader: Remove unused code

dwarf-reader: Remove unused code

Cleanup code that is never used to reduce overall compiled code and
complexity. Some are leftovers from prior refactorings, some are unused
overloads where the more suitable overload is still left.

	* src/abg-dwarf-reader.cc
	(lookup_public_variable_symbol_from_elf): Delete.
	(read_context::bss_section_): Delete.
	(read_context::text_section_): Delete.
	(read_context::rodata_section_): Delete.
	(read_context::data_section_): Delete.
	(read_context::data1_section_): Delete.
	(read_context::initialize): Remove initializations of deleted members.
	(read_context::options): Delete.
	(read_context::bss_section): Delete.
	(read_context::text_section): Delete.
	(read_context::rodata_section): Delete.
	(read_context::data_section): Delete.
	(read_context::data1_section): Delete.
	(read_context::get_elf_file_type): Delete.
	(read_context::lookup_symbol_from_elf): Delete.
	(read_context::lookup_public_variable_symbol_from_elf): Delete.
	(read_context::fun_addr_sym_map_sptr): Delete.
	(read_context::fun_addr_sym_map): Delete.
	(read_context::get_data_section_for_variable_address): Delete.
	(read_context::suppression_matches_function_sym_name): Delete.
	(read_context::suppression_matches_function_name): Delete.
	(read_context::suppression_matches_type_name): Delete.

Signed-off-by: Matthias Maennich <maennich@google.com>