drm/sti: Run DRM default client setup

Call drm_client_setup() to run the kernel's default client setup
for DRM. Set fbdev_probe in struct drm_driver, so that the client
setup can start the common fbdev client.

The sti driver specifies a preferred color mode of 32. As this
is the default if no format has been given, leave it out entirely.

v5:
- select DRM_CLIENT_SELECTION

Signed-off-by: Thomas Zimmermann <[e-mail]>
Cc: Alain Volmat <[e-mail]>
Acked-by: Javier Martinez Canillas <[e-mail]>
Link: https://patchwork.freedesktop.org/patch/msgid/[e-mail]

drivers/gpu/drm/sti/Kconfig

···
 	tristate "DRM Support for STMicroelectronics SoC stiH4xx Series"
 	depends on OF && DRM && (ARCH_STI || COMPILE_TEST)
 	select RESET_CONTROLLER
+	select DRM_CLIENT_SELECTION
 	select DRM_KMS_HELPER
 	select DRM_GEM_DMA_HELPER
 	select DRM_PANEL

drivers/gpu/drm/sti/sti_drv.c

···
 
 #include <drm/drm_atomic.h>
 #include <drm/drm_atomic_helper.h>
+#include <drm/drm_client_setup.h>
 #include <drm/drm_debugfs.h>
 #include <drm/drm_drv.h>
 #include <drm/drm_fbdev_dma.h>
···
 	.driver_features = DRIVER_MODESET | DRIVER_GEM | DRIVER_ATOMIC,
 	.fops = &sti_driver_fops,
 	DRM_GEM_DMA_DRIVER_OPS,
+	DRM_FBDEV_DMA_DRIVER_OPS,
 
 	.debugfs_init = sti_drm_dbg_init,
 
···
 
 	drm_mode_config_reset(ddev);
 
-	drm_fbdev_dma_setup(ddev, 32);
+	drm_client_setup(ddev, NULL);
 
 	return 0;