ada: Fix comment about operational aspects

ada: Fix comment about operational aspects

The comment this patch changes claimed that operational aspects are
"view-specific". The following excerpt from ARM 13.1 (11/5) indicates
that the set of view-specific aspects is in fact much more restricted:

    If a type-related aspect is defined for the partial view of a type,
    then it has the same definition for the full view of the type, except
    for certain Boolean-valued operational aspects where the language
    specifies that the partial view can have the value False even when
    the full view has the value True.

On the other hand, a feature of operational aspects is that they can be
specified on partial views, unlike representation aspects. That's stated
by AARM 13.1 (9.c/1):

    Unlike representation items, operational items can be specified on
    partial views.

So this patch changes the comment to be about that instead.

gcc/ada/ChangeLog:

	* aspects.ads: Fix comment.