[media] drx-j: Avoid any regressions by preserving old behavior

The version is initialized with zero at drx_driver.c. Keep it,
in order to avoid the risk of causing any regression.

While here, remove the drx_driver.h from drxj, as this is not
required there.

Acked-by: Devin Heitmueller <dheitmueller@kernellabs.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>