opr: Libtool archive should depend on symbol file

opr: Libtool archive should depend on symbol file

There should be a dependency between the libtool archive
liboafs_opr.la and the symbol map for the archive
(liboafs_opr.la.sym) so the archive is rebuilt if symbols are added
to, or removed from, the map file.

Change-Id: Ifb0cd0a8abaa4c9b476c53cf186458ec0b8f8778
Reviewed-on: http://gerrit.openafs.org/8107
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Derrick Brashear <shadow@your-file-system.com>