ada: Missing style check for extra parentheses in operators

ada: Missing style check for extra parentheses in operators

This patch fixes an issue in the compiler whereby wrapping an operand
of a boolean operator resulted in a failure to detect whether or not
they were unnecessary for the -gnatyx style checks.

gcc/ada/

	* ali.adb (Get_Nat): Remove unnecessary parentheses.
	* exp_ch11.adb (Expand_Local_Exception_Handlers): Remove
	unnecessary parentheses.
	* freeze.adb (Freeze_Entity): Remove unnecessary parentheses.
	* lib-list.adb (List): Remove unnecessary parentheses.
	* par-ch5.adb (P_Condition): Add extra parentheses checks on
	condition operands.
	* sem_ch3.adb (Add_Interface_Tag_Components): Remove unnecessary
	parentheses.
	(Check_Delta_Expression): Remove unnecessary parenthesis.
	(Check_Digits_Expression): Remove unnecessary parentheses.
	* sem_ch12.adb (Validate_Array_Type_Instance): Remove unnecessary
	parentheses.