* igen.c (main): Change -I to add include paths for :include:
files.
Implement -G as per sim/igen, with just gen-icache=N support.
Call load_insn_table() with the built include path.
* ld-insn.c (parse_include_entry): New. Load an :include: file.
(load_insn_table): New `includes' argument. Look for :include:
entries and call parse_include_entry() for them.
(main): Adjust load_insn_table() call.
* ld-insn.h (model_include_fields): New enum.
(load_insn_table): Update prototype.
* table.c (struct _open_table, struct _table): Rework
structures to handle included files.
(table_push): Move the guts of table_open() here.
* table.c (struct _open table, struct table): Make table object an
indirect ptr to the current table file.
(current_line, new_table_entry, next_line): Make file arg type
open_table.
(table_open): Use table_push.
(table_entry_read): Point variable file at current table, at eof, pop
last open table.
* misc.h (NZALLOC): New macro. From sim/igen.
* table.h, table.c (table_push): New function.
