remove unnecessary startScan logic.

remove unnecessary startScan logic.

it doesn't need to scan when disconnected LE anymore.
since scenario was changed for support manual disconnect API.

Change-Id: I9fb36953d0dc209f7c7dda5c8ad2a3a05b61f0cb
Signed-off-by: jihwan.seo <jihwan.seo@samsung.com>
Reviewed-on: https://gerrit.iotivity.org/gerrit/7499
Tested-by: jenkins-iotivity <jenkins-iotivity@opendaylight.org>
Reviewed-by: Ashok Babu Channa <ashok.channa@samsung.com>
(cherry picked from commit 00c308854d882d4be3c35438b293b7b34ee850ef)
Reviewed-on: https://gerrit.iotivity.org/gerrit/7517
Reviewed-by: Jon A. Cruz <jon@joncruz.org>