gdb: recognize new DWARF attributes: defaulted, deleted, calling conv.

gdb: recognize new DWARF attributes: defaulted, deleted, calling conv.

Extend GDB's internal representation of types to include the
DW_AT_calling_convention, DW_AT_defaulted, and DW_AT_deleted attributes
that were introduced in DWARF5.

These attributes will be helpful in a future patch about infcall'ing
functions with call-by-value parameters.  GDB will use the attributes
to decide whether the type of a call-by-value parameter is implicitly
pass-by-reference.

gdb/ChangeLog:
2019-12-20  Tankut Baris Aktemur  <tankut.baris.aktemur@intel.com>

	* dwarf2read.c (dwarf2_add_member_fn): Read the DW_AT_defaulted
	and DW_AT_deleted attributes of a function.
	(read_structure_type): Read the DW_AT_calling_convention attribute
	of a type.
	(is_valid_DW_AT_defaulted): New function.
	(is_valid_DW_AT_calling_convention_for_type): New function.
	* gdbtypes.h: Include dwarf2.h.
	(struct fn_field)<defaulted>: New field to store the
	DW_AT_defaulted attribute.
	(struct fn_field)<is_deleted>: New field to store the
	DW_AT_deleted attribute.
	(struct cplus_struct_type)<calling_convention>: New field to store
	the DW_AT_calling_convention attribute.
	(TYPE_FN_FIELD_DEFAULTED): New macro.
	(TYPE_FN_FIELD_DELETED): New macro.
	(TYPE_CPLUS_CALLING_CONVENTION): New macro.
	* gdbtypes.c (dump_fn_fieldlists): Update for the changes made
	to the .h file.
	(print_cplus_stuff): Likewise.

Change-Id: I54192f363115b78ec7435a8563b73fcace420765