[PATCH 04/11] Handle pointers for CodeView

[PATCH 04/11] Handle pointers for CodeView

Translates DW_TAG_pointer_type DIEs into LF_POINTER symbols, which get
output into the .debug$T section.

gcc/
	* dwarf2codeview.cc (FIRST_TYPE): Define.
	(struct codeview_custom_type): New structure.
	(custom_types, last_custom_type): New variables.
	(get_type_num): Prototype.
	(write_lf_pointer, write_custom_types): New functions.
	(codeview_debug_finish): Call write_custom_types.
	(add_custom_type, get_type_num_pointer_type): New functions.
	(get_type_num): Handle DW_TAG_pointer_type DIEs.
	* dwarf2codeview.h (T_VOID): Define.
	(CV_POINTER_32, CV_POINTER_64): Likewise.
	(T_32PVOID, T_64PVOID): Likewise.
	(CV_PTR_NEAR32, CV_PTR64, LF_POINTER): Likewise.