[PR libgomp/64625] Remove __OFFLOAD_TABLE__ variable/formal parameter.

[PR libgomp/64625] Remove __OFFLOAD_TABLE__ variable/formal parameter.

	gcc/
	* omp-low.c (offload_symbol_decl): Remove variable.
	(get_offload_symbol_decl): Remove function.
	(expand_omp_target): For BUILT_IN_GOMP_TARGET,
	BUILT_IN_GOMP_TARGET_DATA, BUILT_IN_GOMP_TARGET_UPDATE pass NULL
	instead of &__OFFLOAD_TABLE__, for BUILT_IN_GOACC_DATA_START,
	BUILT_IN_GOACC_ENTER_EXIT_DATA, BUILT_IN_GOACC_PARALLEL,
	BUILT_IN_GOACC_UPDATE don't pass it at all.
	libgomp/
	* libgomp_g.h (GOACC_data_start, GOACC_enter_exit_data)
	(GOACC_parallel, GOACC_update): Remove const_void *offload_table
	formal parameter.  Update all users.
	* target.c (GOMP_target, GOMP_target_data, GOMP_target_update):
	Document unused formal parameter.

From-SVN: r219837