[media] solo6x10: sync to latest code from Bluecherry's git repo

Synced to commit e9815ac5503ae60cfbf6ff8037035de8f62e2846 from
branch next in git repository https://github.com/bluecherrydvr/solo6x10.git
Only removed some code under #if LINUX_VERSION_CODE < some-kernel-version,
renamed the driver back to solo6x10 from solo6x10-edge, removed the
unnecessary compat.h header and kept the slab.h includes.
Otherwise the code is identical.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Ismael Luceno <ismael.luceno@corp.bluecherry.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>