remove unneeded declaration of .generic_bulk_ctrl_endpoint

generic_bulk_ctrl_endpoint isn't being used in this device, so this
is not needed here.
Signed-off-by: NMichael Krufky <mkrufky@linuxtv.org>
Signed-off-by: NMauro Carvalho Chehab <mchehab@infradead.org>