lwp: rw now depends on libopr

rw (a test program for lwp) needs libopr to build

Change-Id: I489e675f5a1b845c7a8083466b44a73af305f8b8
Reviewed-on: http://gerrit.openafs.org/10517
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Jeffrey Altman <jaltman@your-file-system.com>