Followup to r14646. The symbol TIOCSIG is not necessarily defined,
e.g. on s390x with glibc 2.3.4. Modify the testcase to bypass the ioctl
call in that case.


git-svn-id: svn://svn.valgrind.org/valgrind/trunk@14649 a5019735-40e9-0310-863c-91ae7b9d1cf9
Change the initialisation of the newly allocated struct sched_lock
object. Just memset the whole thing to 0. That avoids a cast that
drops type qualifiction.


git-svn-id: svn://svn.valgrind.org/valgrind/trunk@14650 a5019735-40e9-0310-863c-91ae7b9d1cf9