IOT-2495 Fixed linking issue with BT connectivity

IOT-2495 Fixed linking issue with BT connectivity

The library connectivity_abstraction_internal does not work
for android if bluetooth is used. It must be linked with
connectivity_abstraction.
Windows still needs to link against
connectivity_abstraction_internal.

Bug: https://jira.iotivity.org/browse/IOT-2495

Change-Id: I357969543313199615ceac3b3b5e5b9f6b7f4b48
Signed-off-by: George Nash <george.nash@intel.com>
Reviewed-on: https://gerrit.iotivity.org/gerrit/21411
Tested-by: jenkins-iotivity <jenkins@iotivity.org>
Reviewed-by: Larry Sachs <larry.j.sachs@intel.com>
Reviewed-by: Md. Adnan Sami <adnan.sami@samsung.com>
Reviewed-by: Rick Bell <richard.s.bell@intel.com>