[PATCH] Ensure zero termination in string/test-s*.c (was Re: segfault in test-strcmp)

[Roland McGrath]

Thanks!  I have put these changes in.  The tests now pass on powerpc.

Btw, I had previously changed test-string.h to fill the BUF1 and BUF2 pages
with nonzero bytes so as to detect any fail-to-terminate kinds of bugs,
which seemed like a good idea when this first came up.  Doing that now
breaks several tests though they seem to be correct now, so I didn't put it in.