treewide: Add SPDX license identifier - Makefile/Kconfig

Add SPDX license identifiers to all Make/Kconfig files which:

- Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[media] Add support for TechniSat Skystar S2

This patch adds support for the Technisat Skystar S2 - this
has been tried before but the cx24120 driver was a bit out of shape
and it didn't got any further:

https://patchwork.linuxtv.org/patch/10575/

It is an old card, but currently being sold off for next to nothing,
so it's proving quite popular of late. Noticing it's quite similar
to the cx24116 and cx24117 I've rewritten the driver in a similar way.

There were a few registers and commands from those drivers
missing from this one I've tested out and found they do something so
they've been added in to speed up tuning and to make get_frontend
return something useful.

Signed-off-by: Jemma Denson <jdenson@gmail.com>
Signed-off-by: Patrick.Boettcher <patrick.boettcher@posteo.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

[media] common/*/Kconfig: Remove unused helps

Those items don't have any menu anymore; they're auto-selected by
USB/PCI/MMC drivers. So, there's no sense on keeping any help
there anymore.

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

[media] flexcop: Show the item to enable debug after the driver

Instead of showing the option to show debug at the end, show
it after each driver.

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

[media] Kconfig: merge all customise options into just one

Instead of having 3 options to allow customizing the media
sub-drivers (tuners, I2C drivers, frontends), merge all of
them into just one.

That simplifies the life for users, as they can just keep
this untouched.

Life for developers is also simpler, as there's now just
one Kconfig item to remember, for the ancillary sub-drivers
providing supports for chips that could change from one
board design to another.

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

[media] b2c2: break it into common/pci/usb directories

b2c2 is, in fact, 2 drivers: one for PCI and one for USB, plus
a common bus-independent code. Break it accordingly.

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>