Add helgrind intercepts to have helgrind understanding Ada tasks terination rules
A recent gnatpro version is needed for this to work.

Thanks to these intercepts, some false positive errors are avoided,
and helgrind properly recuperates some internal memory associated
to the terminated task.



git-svn-id: svn://svn.valgrind.org/valgrind/trunk@14046 a5019735-40e9-0310-863c-91ae7b9d1cf9