package/ell: bump version to 0.39

Changelog:
https://git.kernel.org/pub/scm/libs/ell/ell.git/tree/ChangeLog

Needed for bluez5_utils bump to 5.58:
http://www.bluez.org/release-of-bluez-5-58-and-5-57/



Signed-off-by: Bernd Kuhls <bernd.kuhls@t-online.de>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>