[Ada] Incremental patch for restriction No_Dynamic_Accessibility_Checks

[Ada] Incremental patch for restriction No_Dynamic_Accessibility_Checks

gcc/ada/

	* doc/gnat_rm/standard_and_implementation_defined_restrictions.rst:
	Add new entry for No_Dynamic_Accessibility_Checks documenting
	behavior.
	* gnat_rm.texi: Regenerate.
	* exp_ch4.adb (Expand_N_In): Perform special expansion for
	membership tests when No_Dynamic_Accessibility_Checks is active.
	* sem_attr.adb (Resolve_Attribute): Skip static accessibility
	check on actuals for anonymous access type formal parameters,
	and add constants for readability.
	* sem_util.adb (Function_Call_Or_Allocator_Level): Use the
	innermost master for determining the level for function calls
	within the alternative accessibility model.
	(Type_Access_Level): Properly get the level for anonymous access
	function result types.