IPCA: Install libipca dir to libdir

IPCA: Install libipca dir to libdir

It needs to be install to variant dir along other libs then
dependency libs will be also be found using RPATH.

Bug: https://jira.iotivity.org/browse/IOT-1745
Change-Id: I4e9ff5ad8b72850f5ef79a093502edf53c8e64d7
Signed-off-by: Philippe Coval <philippe.coval@osg.samsung.com>
Reviewed-on: https://gerrit.iotivity.org/gerrit/21891
Tested-by: jenkins-iotivity <jenkins@iotivity.org>
Reviewed-by: Dan Mihai <Daniel.Mihai@microsoft.com>
(cherry picked from commit 811ad50df741db60420cd2415ad8c94378cd79f1)