[IOT-1320] Make SECURED flag default '1'

[IOT-1320] Make SECURED flag default '1'

Note:
  arduino does not support build with SECURED=1 see IOT-1331
  Darwin and iOS built with SECURED=0 see IOT-1684

Change-Id: I87c7c0e76423c4f58f8dbea911835f27b2936a0b
Signed-off-by: George Nash <george.nash@intel.com>
Reviewed-on: https://gerrit.iotivity.org/gerrit/12085
Tested-by: jenkins-iotivity <jenkins-iotivity@opendaylight.org>
Reviewed-by: Greg Zaverucha <gregz@microsoft.com>
Reviewed-by: Uze Choi <uzchoi@samsung.com>
Reviewed-by: Dave Thaler <dthaler@microsoft.com>
Reviewed-by: Randeep Singh <randeep.s@samsung.com>