drm/gem: rename GEM CMA helpers to GEM DMA helpers

Rename "GEM CMA" helpers to "GEM DMA" helpers - considering the
hierarchy of APIs (mm/cma -> dma -> gem dma) calling them "GEM
DMA" seems to be more applicable.

Besides that, commit e57924d4ae80 ("drm/doc: Task to rename CMA helpers")
requests to rename the CMA helpers and implies that people seem to be
confused about the naming.

In order to do this renaming the following script was used:

```
#!/bin/bash

DIRS="drivers/gpu include/drm Documentation/gpu"

REGEX_SYM_UPPER="[0-9A-Z_\-]"
REGEX_SYM_LOWER="[0-9a-z_\-]"

REGEX_GREP_UPPER="(${REGEX_SYM_UPPER}*)(GEM)_CMA_(${REGEX_SYM_UPPER}*)"
REGEX_GREP_LOWER="(${REGEX_SYM_LOWER}*)(gem)_cma_(${REGEX_SYM_LOWER}*)"

REGEX_SED_UPPER="s/${REGEX_GREP_UPPER}/\1\2_DMA_\3/g"
REGEX_SED_LOWER="s/${REGEX_GREP_LOWER}/\1\2_dma_\3/g"

# Find all upper case 'CMA' symbols and replace them with 'DMA'.
for ff in $(grep -REHl "${REGEX_GREP_UPPER}" $DIRS)
do
sed -i -E "$REGEX_SED_UPPER" $ff
done

# Find all lower case 'cma' symbols and replace them with 'dma'.
for ff in $(grep -REHl "${REGEX_GREP_LOWER}" $DIRS)
do
sed -i -E "$REGEX_SED_LOWER" $ff
done

# Replace all occurrences of 'CMA' / 'cma' in comments and
# documentation files with 'DMA' / 'dma'.
for ff in $(grep -RiHl " cma " $DIRS)
do
sed -i -E "s/ cma / dma /g" $ff
sed -i -E "s/ CMA / DMA /g" $ff
done

# Rename all 'cma_obj's to 'dma_obj'.
for ff in $(grep -RiHl "cma_obj" $DIRS)
do
sed -i -E "s/cma_obj/dma_obj/g" $ff
done
```

Only a few more manual modifications were needed, e.g. reverting the
following modifications in some DRM Kconfig files

- select CMA if HAVE_DMA_CONTIGUOUS
+ select DMA if HAVE_DMA_CONTIGUOUS

as well as manually picking the occurrences of 'CMA'/'cma' in comments and
documentation which relate to "GEM CMA", but not "FB CMA".

Also drivers/gpu/drm/Makefile was fixed up manually after renaming
drm_gem_cma_helper.c to drm_gem_dma_helper.c.

This patch is compile-time tested building a x86_64 kernel with
`make allyesconfig && make drivers/gpu/drm`.

Acked-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Danilo Krummrich <dakr@redhat.com>
Reviewed-by: Liviu Dudau <liviu.dudau@arm.com> #drivers/gpu/drm/arm
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220802000405.949236-4-dakr@redhat.com

drm: Remove CONFIG_DRM_KMS_CMA_HELPER option

Link drm_fb_cma_helper.o into drm_cma_helper.ko if CONFIG_DRM_KMS_HELPER
has been set. Remove CONFIG_DRM_KMS_CMA_HELPER config option. Selecting
KMS helpers and CMA will now automatically enable CMA KMS helpers.

Some drivers' Kconfig files did not correctly select KMS or CMA helpers.
Fix this as part of the change.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20211106193509.17472-3-tzimmermann@suse.de

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/atmel-hlcdc: make fbdev support really optional

Currently enabling ATMEL HLCDC DRM support automatically pulls
in fbdev dependency. However this dep is unnecessary since
DRM core already handles this for us (DRM_FBDEV_EMULATION).

Signed-off-by: Tobias Jakobi <tjakobi@math.uni-bielefeld.de>
Signed-off-by: Sean Paul <seanpaul@chromium.org>

drm: atmel-hlcdc: Add dependency on ARM

The atmel-hlcdc driver selects DRM_GEM_CMA_HELPER which makes use of
symbols only available when HAVE_DMA_ATTRS is selected.
Add a dependency on the ARM architecture which select this option.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Dave Airlie <airlied@gmail.com>

drm: add Atmel HLCDC Display Controller support

The Atmel HLCDC (HLCD Controller) IP available on some Atmel SoCs (i.e.
at91sam9n12, at91sam9x5 family or sama5d3 family) provides a display
controller device.

This display controller supports at least one primary plane and might
provide several overlays and an hardware cursor depending on the IP
version.

At the moment, this driver only implements an RGB connector to interface
with LCD panels, but support for other kind of external devices might be
added later.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Tested-by: Anthony Harivel <anthony.harivel@emtrion.de>
Tested-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>