Enable prctl on ppc64-linux.  Fixes #308089.


git-svn-id: svn://svn.valgrind.org/valgrind/trunk@13350 a5019735-40e9-0310-863c-91ae7b9d1cf9
Don't assume that page size is 4K when loading PIEs.  Fixes #263034.
(Dodji Seketeli, dodji@redhat.com)


git-svn-id: svn://svn.valgrind.org/valgrind/trunk@13351 a5019735-40e9-0310-863c-91ae7b9d1cf9