nptl/tst-setuid3.c was using the `err' and `errx' functions to write
error messages. This wrote to stderr instead of the preferred stdout.

This patch should fix that.

ChangeLog:

2014-09-19  Arjun Shankar  <arjun.is@lostca.se>

	* nptl/tst-setuid3.c: Write errors to stdout.
---
 nptl/tst-setuid3.c | 36 +++++++++++++++++++++---------------
 1 file changed, 21 insertions(+), 15 deletions(-)

Changes in v2:
 - incorporate Florian's review comment: use %m to write errno string;
   Note: Seems there are many tests that write to stderr. I will look
   at them during the coming week(s) when I find a good chunk of time.