services: core: wfd: extend check for qualcomm wfd jar

Some BSPs have moved WfdCommon.jar out of the boot classpath
and moved it to /system_ext/framework/.

Check the new location if the initial lookup fails.

Change-Id: I78dff4bc649970e6c5608ae03f1789e30fc95c2f
Signed-off-by: Alexander Martinz <amartinz@shiftphones.com>