Fix configure probe for sys/ucred.h.
The configure script's test for <sys/ucred.h> did not work on OpenBSD,
because on that platform <sys/param.h> has to be included first.
As a result, socket peer authentication was disabled on that platform.
Problem introduced in commit be4585b1c27ac5dbdd0d61740d18f7ad9a00e268.
Andres Freund, slightly simplified by me.
Branch
------
master
Details
-------
http://git.postgresql.org/pg/commitdiff/1b09630fce1dfd4116eaaf154766a8a435168193
Modified Files
--------------
configure | 76 ++++++++++++++++++++++++++++++++++++++++++++++++++++++----
configure.in | 14 ++++++++---
2 files changed, 83 insertions(+), 7 deletions(-)
