afsmonitor: Add missing items to fsOpNames array

The Lookup and Residency fs stats counters were missing from the
fsOpNames array. Add them in - Lookup has been missing since the
IBM release, Residency was missed when the MR-AFS code was merged.

This is still rather fragile, as there's no guarantee that
AFS_STATS_NUM_FS_RPC_OPS matches the number of elements in this
array. However, this is now correct until someone breaks it again...

Caught by coverity (#985569)

Reviewed-on: http://gerrit.openafs.org/9314
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Jeffrey Altman <jaltman@your-file-system.com>
(cherry picked from commit 74d0d0d5e686d82e18f896889870af666c4d495d)

Change-Id: Iac7275fd9dd9a2fa5fe163ba96a15d32d4e5d05e
Reviewed-on: http://gerrit.openafs.org/11027
Reviewed-by: Chas Williams - CONTRACTOR <chas@cmf.nrl.navy.mil>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Andrew Deason <adeason@sinenomine.net>
Reviewed-by: Stephan Wiesand <stephan.wiesand@desy.de>