liboc: add missing depending library

liboc: add missing depending library

liboc.so depends on liboctbstack.so, liboc_logger.so and pthread, this
patch adds these dependencies to the build.

Without this the dynamic loader will not automatically load these
libraries and it could result in unresolved dependencies at runtime.

Change-Id: I971b45669adef31dc9cca719884ebeb74aaf735e
Signed-off-by: Hauke Mehrtens <hauke.mehrtens@lantiq.com>
Reviewed-on: https://gerrit.iotivity.org/gerrit/1794
Tested-by: jenkins-iotivity <jenkins-iotivity@opendaylight.org>
Reviewed-by: Erich Keane <erich.keane@intel.com>