Conversion of lmedm04 to dvb-usb-v2

Functional changes m88rs2000 tuner now uses all callbacks.
TODO migrate other tuners to the callbacks.

This patch is applied on top of [BUG] Re: dvb_usb_lmedm04 crash Kernel (rs2000)
http://patchwork.linuxtv.org/patch/13584/Signed-off-by: NMalcolm Priestley <tvboxspy@gmail.com>
Acked-by: NAntti Palosaari <crope@iki.fi>
Tested-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>