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>

drm/stm: Add STM32 DSI controller driver

Add the STM32 DSI controller driver that uses the Synopsys DesignWare
MIPI DSI host controller bridge.

Signed-off-by: Philippe CORNU <philippe.cornu@st.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Archit Taneja <architt@codeaurora.org>
Signed-off-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/1500277223-29553-8-git-send-email-philippe.cornu@st.com

drm/stm: remove unneeded -Iinclude/drm compiler flag

With the include directives under include/drm/ fixed, this flag is
no longer needed.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1495081793-9707-13-git-send-email-yamada.masahiro@socionext.com

drm/stm: Add STM32 LTDC driver

This controller provides output signals to interface directly a variety
of LCD and TFT panels. These output signals are: RGB signals
(up to 24bpp), vertical & horizontal synchronisations, data enable and
the pixel clock.

Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Yannick Fertre <yannick.fertre@st.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
Link: http://patchwork.freedesktop.org/patch/msgid/1492164819-10513-5-git-send-email-yannick.fertre@st.com
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Eric Anholt <eric@anholt.net>