Corrected DB query of PDM

Corrected DB query of PDM

To check the existence of link between two devices, We should use query with
‘and’ not ‘or’.
Previously link  was checked with ‘or’ thats why if we try to create multiple
links involving one same device and other different devices then it was showing
link already exists. for example if we create link between A-B then if we try
to create link between A-C then we are getting error that link already exists.

Change-Id: I408658af4f423a641bab077439435711ecac876e
Signed-off-by: Randeep Singh <randeep.s@samsung.com>
Reviewed-on: https://gerrit.iotivity.org/gerrit/3361
Reviewed-by: Woochul Shim <woochul.shim@samsung.com>
Tested-by: jenkins-iotivity <jenkins-iotivity@opendaylight.org>
Reviewed-by: Sachin Agrawal <sachin.agrawal@intel.com>