package/xbmc: remove spurious build-dependency on udev

CEC support with libcec needs udev, but it is the responsibility
of libcec to have proper build-dependencies, not XBMC.

So, just remove the spurious dependency on udev in XBMC.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Acked-by: Bernd Kuhls <bernd.kuhls@t-online.de>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>