[SSM] Fix issue about initializing SSM with invalid parameter (IOT-260)

[SSM] Fix issue about initializing SSM with invalid parameter (IOT-260)

Modify SoftSensorManager to return error code when initialized with invalid parameter

Change-Id: Ia0a54cd6e71321cbe2b4fd18352a2a609c20fabd
Signed-off-by: Minji Park <minjii.park@samsung.com>
Reviewed-on: https://gerrit.iotivity.org/gerrit/229
Tested-by: jenkins-iotivity <jenkins-iotivity@opendaylight.org>
Reviewed-by: Uze Choi <uzchoi@samsung.com>
(cherry picked from commit ef380650f9c35120091c36b44c974c3d3712e91d)
Reviewed-on: https://gerrit.iotivity.org/gerrit/376
Reviewed-by: Sudarshan Prasad <sudarshan.prasad@intel.com>