[Device] Fix dlr_device_set_position implementation
[Device] Fix dlr_device_set_position implementation

dlr_device_set_position is incorrectly implemented.
now we use the REL_TIME unit for Time based Seeking
instead of ABS_TIME unit and the X_DLNA_REL_BYTE unit for
Byte Seeking instead of ABS_COUNT unit.

Partial fix for issue:

https://github.com/01org/dleyna-renderer/issues/115

Signed-off-by: Christophe Guiraud <30357c354beb4bc5af68caf67885eac30efd53cc@intel.com>

01org/dleyna-renderer,UIKit0/dleyna-renderer,jku/dleyna-renderer,debarshiray/dleyna-renderer,01org/dleyna-renderer,KobaltRo/dleyna-renderer,01org/dleyna-renderer,jku/dleyna-renderer,lferrandis/dleyna-renderer,puleglot/dleyna-renderer,jku/dleyna-renderer,debarshiray/dleyna-renderer,debarshiray/dleyna-renderer,lferrandis/dleyna-renderer,KobaltRo/dleyna-renderer,UIKit0/dleyna-renderer,rmerlino/dleyna-renderer,rmerlino/dleyna-renderer,UIKit0/dleyna-renderer,puleglot/dleyna-renderer,lferrandis/dleyna-renderer,01org/dleyna-renderer,debarshiray/dleyna-renderer,rmerlino/dleyna-renderer,lferrandis/dleyna-renderer,rmerlino/dleyna-renderer,puleglot/dleyna-renderer,KobaltRo/dleyna-renderer