Fix up r298368

Remove the semicolon accidentally added after the new conditional that tests
that /dev/zero is opened successfully.

MFC after: 1 week
X-MFC with: r298368
Pointhat to: ngie
Reported by: Coverity
CID: 1354980
Sponsored by: EMC / Isilon Storage Division

Fix coverity issue with contrib/netbsd-tests/lib/libc/ssp/h_read.c

Ensure opening /dev/zero succeeds. Abort the test if it doesn't.

Also, use _PATH_DEVZERO instead of hardcoding "/dev/zero"

MFC after: 2 weeks
CID: 1251410
Reported by: Coverity
Sponsored by: EMC / Isilon Storage Division"

Port lib/libc/ssp to FreeBSD

In most cases, the buffers and data were resized, but when dealing with the
helpers, some of the code was adjusted to fail more reliably

Submitted by: pho