comerr, cmd, opr: fix library install targets

comerr, cmd, opr: fix library install targets

Fix a couple of issues in the install targets following the libtool
changes:
- don't install liboafs_comerr or liboafs_opr, they're not ready to
be exposed to the outside world
- fix the libcmd.a install target to use INSTALL_DATA and the correct
library name

Change-Id: I2bf241cfff419d51bf170fdc871248e9b0c7ab33
Reviewed-on: http://gerrit.openafs.org/8063
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Simon Wilkinson <simonxwilkinson@gmail.com>
Reviewed-by: Derrick Brashear <shadow@your-file-system.com>