Include afsconfig.h before anything else

Include afsconfig.h before anything else

afsconfig.h can define various preprocessor symbols that can affect
how system headers behave. For example, the presence of the
_POSIX_PTHREAD_SEMANTICS symbol changes the number of arguments to
getpwnam_r on at least Solaris 8. So, we must include afsconfig.h
before including anything else, to ensure consistency.

FIXES 130413

Reviewed-on: http://gerrit.openafs.org/6387
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Jeffrey Altman <jaltman@secure-endpoints.com>
(cherry picked from commit 37f537a21db6d560dd16a53ff5e0d2f0456d4c48)

Change-Id: I64970fd06af9a13d91acaf03b80a2baf224754ff
Reviewed-on: http://gerrit.openafs.org/6388
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Jeffrey Altman <jaltman@secure-endpoints.com>