afs: remove commented out AIX specific tweak

afs: remove commented out AIX specific tweak

This AIX specific code block has been commented out since
openafs-ibm-1_0.  The comments seem to indicate this was a networking
tweak specific to AIX, but the kernel variables involved were not
exported.  Clean up afs_call.c by removing this dead code.

Reviewed-on: https://gerrit.openafs.org/12276
Reviewed-by: Benjamin Kaduk <kaduk@mit.edu>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
(cherry picked from commit 5277460eaa300fc973b59d007cd3eaea93d30873)

Change-Id: Idcf94dc5962a6bb183af3bfccead3b17cff2ee58
Reviewed-on: https://gerrit.openafs.org/12306
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Mark Vitale <mvitale@sinenomine.net>
Reviewed-by: Michael Meffie <mmeffie@sinenomine.net>
Reviewed-by: Stephan Wiesand <stephan.wiesand@desy.de>