ada: Compiler crash on ill-formed container indexing

ada: Compiler crash on ill-formed container indexing

The compiler blows up when analyzing an illegal indexing of a container
object (such as a vector) when the indexing expression has the form of
a named actual parameter and the name given for the parameter does not
match the name of the index formal of the corresponding indexing function
that the compiler identifies for doing the generalized indexing.

gcc/ada/ChangeLog:

	* sem_ch4.adb (Try_Container_Indexing): Conditionalize last actual of
	call to Error_Msg_NE to avoid blowup on N_Parameter_Association actuals.