tests: Make deleted and vdsosyms testcases work with "restricted ptrace".

tests: Make deleted and vdsosyms testcases work with "restricted ptrace".

Some systems might have "restricted ptrace" that doesn't allow process
inspection of arbitrary processes. Change the deleted testcase to
explicitly allow any other process to inspect it using the PR_SET_PTRACER
prctl set to PR_SET_PTRACER_ANY. Change the vdsosyms testcase to inspect
the process itself which should always be allowed.

Reported-by: Anatol Pomozov <anatol.pomozov@gmail.com>
Signed-off-by: Mark Wielaard <mjw@redhat.com>