Symbols with octets value

Symbols with octets value

Up to now, all symbol values are in units of bytes, where a "byte" can
consist of one or more octets (e.g. 8 bit or 16 bit).

Allow to specfiy that the "unit" of a newly created symbol is octets
(exactly 8 bit), instead of bytes.

	* symbols.h (symbol_temp_new_now_octets): Declare.
	(symbol_set_value_now_octets, symbol_octets_p): Declare.
	* symbols.c (struct symbol_flags): New member sy_octets.
	(symbol_temp_new_now_octets): New function.
	(resolve_symbol_value): Return octets instead of bytes if
	sy_octets is set.
	(symbol_set_value_now_octets): New function.
	(symbol_octets_p): New function.