[IOT-1519] Don't clear ownerPSK secret too early
[IOT-1519] Don't clear ownerPSK secret too early

Owner PSK secret was cleared too early; only clear after
all uses are finished.

Change-Id: Ie39990a5aabfcd71b8370103b7182cb76cb09f40
Signed-off-by: Kevin Kane <cd40c34e976f30c9e62efcf24e04c516bc3a3b05@microsoft.com>
Reviewed-on: https://gerrit.iotivity.org/gerrit/14491
Tested-by: jenkins-iotivity <09cb29e8a2b473a2c978382eec13ee06fa017bda@opendaylight.org>
Reviewed-by: Uze Choi <3a26c91d8a4a3c9e246e43339f4782bb2483aece@samsung.com>
Reviewed-by: Jongsung Lee <9c259bfed670402e92d78a50f59fd38cfd576160@samsung.com>
Reviewed-by: Randeep Singh <46ce9385024397d3e4d9ed63be2e0a0d801e95b7@samsung.com>
(cherry picked from commit d07d715c49707a0940cc27f57b128e44954829e8)
Reviewed-on: https://gerrit.iotivity.org/gerrit/14497

iotivity/iotivity,rzr/iotivity,iotivity/iotivity,iotivity/iotivity,iotivity/iotivity,iotivity/iotivity,rzr/iotivity,rzr/iotivity,iotivity/iotivity,rzr/iotivity,iotivity/iotivity,rzr/iotivity,rzr/iotivity,rzr/iotivity,iotivity/iotivity