[IOT-2236] Allow POST to /oic/sec/acl

[IOT-2236] Allow POST to /oic/sec/acl

Restore the old behavior of starting parsing the payload with
ehRet == OC_EH_OK. This behavior has been modified incorrectly
by recent change 170dceb649c7aab72a087feec0b3e37bd8829848.

Change-Id: I13e5aa1e5f3a840668182d36ffb58d309cd8c1ad
Signed-off-by: Dan Mihai <Daniel.Mihai@microsoft.com>
Reviewed-on: https://gerrit.iotivity.org/gerrit/19819
Tested-by: jenkins-iotivity <jenkins@iotivity.org>
Reviewed-by: Kevin Kane <kkane@microsoft.com>
Reviewed-by: Nathan Heldt-Sheller <nathan.heldt-sheller@intel.com>