Convert stap probes to create operations

Convert stap probes to create operations

This changes the stap probe code to create operations, rather than
exp_elements.

gdb/ChangeLog
2021-03-08  Tom Tromey  <tom@tromey.com>

	* stap-probe.c (binop_maker_ftype): New typedef.
	(stap_maker_map): New global.
	(stap_make_binop): New function.
	(stap_parse_register_operand): Return operation_up.
	(stap_parse_single_operand, stap_parse_argument_conditionally)
	(stap_parse_argument_1): Likewise.
	(stap_parse_argument): Create operations.
	(stap_probe::parse_arguments): Update.
	(_initialize_stap_probe): Initialize stap_maker_map.
	* ppc-linux-tdep.c (ppc_stap_parse_special_token): Change return
	type.
	* i386-tdep.h (i386_stap_parse_special_token): Change return
	type.
	* i386-tdep.c (i386_stap_parse_special_token_triplet)
	(i386_stap_parse_special_token_three_arg_disp)
	(i386_stap_parse_special_token): Change return type.
	* gdbarch.sh (stap_parse_special_token): Change return type.
	* gdbarch.c: Rebuild.
	* gdbarch.h: Rebuild.
	* arm-linux-tdep.c (arm_stap_parse_special_token): Change return
	type.
	* aarch64-linux-tdep.c (aarch64_stap_parse_special_token): Change
	return type.