drm/panel-mipi-dbi: 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.

v5:
- select DRM_CLIENT_SELECTION

Signed-off-by: Thomas Zimmermann <[e-mail]>
Cc: "Noralf Trønnes" <[e-mail]>
Acked-by: Noralf Trønnes <[e-mail]>
Link: https://patchwork.freedesktop.org/patch/msgid/[e-mail]

drivers/gpu/drm/tiny/Kconfig

···
 config DRM_PANEL_MIPI_DBI
 	tristate "DRM support for MIPI DBI compatible panels"
 	depends on DRM && SPI
+	select DRM_CLIENT_SELECTION
 	select DRM_KMS_HELPER
 	select DRM_GEM_DMA_HELPER
 	select DRM_MIPI_DBI

drivers/gpu/drm/tiny/panel-mipi-dbi.c

···
 #include <linux/spi/spi.h>
 
 #include <drm/drm_atomic_helper.h>
+#include <drm/drm_client_setup.h>
 #include <drm/drm_drv.h>
 #include <drm/drm_fbdev_dma.h>
 #include <drm/drm_gem_atomic_helper.h>
···
 	.driver_features	= DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC,
 	.fops			= &panel_mipi_dbi_fops,
 	DRM_GEM_DMA_DRIVER_OPS_VMAP,
+	DRM_FBDEV_DMA_DRIVER_OPS,
 	.debugfs_init		= mipi_dbi_debugfs_init,
 	.name			= "panel-mipi-dbi",
 	.desc			= "MIPI DBI compatible display panel",
···
 
 	spi_set_drvdata(spi, drm);
 
-	drm_fbdev_dma_setup(drm, 0);
+	drm_client_setup(drm, NULL);
 
 	return 0;
 }