[Ada] Fix internal error on if-expression in call returning tagged type

[Ada] Fix internal error on if-expression in call returning tagged type

gcc/ada/

	* checks.adb (Determine_Range): Deal with Min and Max attributes.
	* exp_ch6.adb (Expand_Call_Helper): When generating code to pass
	the accessibility level to the caller in the case of an actual
	which is an if-expression, also remove the nodes created after
	the declaration of the dummy temporary.
	* sem_ch6.adb (Analyze_Subprogram_Body_Helper): Use Natural as
	the type of the minimum accessibility level object.