ptest-runner: fix segfault with -t option

ptest-runner: fix segfault with -t option

The ptest-runner would segfault with -t option:
root@qemux86-64:~# ptest-runner -d /usr/lib test_pkg -t 5
[  237.234112] ptest-runner[810]: segfault at 0 ip 000000382e638060 sp
00007fff9130f400 error 4 in libc-2.26.so[382e600000+1a7000]

It is safe to bump SRCREV to latest upstream commit to fix this issue
because there is only one commit since the last update:

  commit 8a93832dad621535e90aa8e1fb74ae5ba743fc3e
  Author: Anders Wallin <wallinux@gmail.com>
  Date:   Sun May 28 11:47:00 2017 +0200

      timeout option missing the argument option ":" to getopt

      ptest-runner -t xx gives segfault

      Signed-off-by: Anders Wallin <wallinux@gmail.com>
      Signed-off-by: Aníbal Limón <anibal.limon@linux.intel.com>
(From OE-Core rev: 503ce98bb89dfa019faff872121c8911e6465b05)

Signed-off-by: Yi Zhao <yi.zhao@windriver.com>
Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>