Hello,

this patch updates the dvb subsystem core.

Fixed problems:
- partly reintroduced the DVB_DEVFS_ONLY switch, which was previously
wiped out by Alan Cox: if enabled, some really obscure code is not
compiled into the kernel that is necessary to xxx
- switched from user-land types like __u8 to u8 and uint16_t to u16
this makes the patch rather large.
- updated the dvr (digital videorecording) facility
- renamed some structures, like "struct dmxdev_s" to "struct dmxdev"
- introduced dvb_functions.[ch], where some linux-kernel specific
functions are encapsulated. by this, the dvb subsystem stays quite
independent from deeper linux kernel functions.
- moved dvb_usercopy() to dvb_functions.c -- this is essentially
video_usercopy() which should be generic_usercopy() instead... ;-)
- Made the dvb-core in dvbdev.c work with devfs again. I had to
introduce some #if KERNELVERSION magic again here, sorry. I'll fix it up
with the next patchset.

Please review and apply.

Thanks
Michael Hunold.