selftest/wic: Improve error message for test_fixed_size

Currently this can fail with a message like 127 != 0 which is unhelpful.

If we remove the ignore_status=False, the debugging from runCmd is much
more helpful printing status.output.

Also remove the now unneeded exit code check.

(From OE-Core rev: 1aa7471b11aedc68de5116c461fe73152e3985fd)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/lib/oeqa/selftest/cases/wic.py

@@ -695,9 +695,7 @@ class Wic2(WicTestCase):
 
         # verify partition size with wic
         res = runCmd("parted -m %s unit mib p 2>/dev/null" % wicimg,
-                     ignore_status=True,
                      native_sysroot=self.native_sysroot)
-        self.assertEqual(0, res.status)
 
         # parse parted output which looks like this:
         # BYT;\n