drm: shmobile: Add missing call to drm_fbdev_generic_setup()

Set up generic fbdev emulation, to enable support for the Linux console.

Use 16 as the preferred depth, as that is a good compromise between
colorfulness and resource utilization, and the default of the fbdev
driver.
Suggested-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/c836938112fda21762bc9eb2741ccd0cbf1197ef.1684854992.git.geert+renesas@glider.be

drivers/gpu/drm/shmobile/shmob_drm_drv.c

@@ -16,6 +16,7 @@
 #include <linux/slab.h>
 
 #include <drm/drm_drv.h>
+#include <drm/drm_fbdev_generic.h>
 #include <drm/drm_gem_dma_helper.h>
 #include <drm/drm_module.h>
 #include <drm/drm_probe_helper.h>
@@ -271,6 +272,8 @@ static int shmob_drm_probe(struct platform_device *pdev)
 	if (ret < 0)
 		goto err_irq_uninstall;
 
+	drm_fbdev_generic_setup(ddev, 16);
+
 	return 0;
 
 err_irq_uninstall: