fbdev/fsl-diu-fb: Use fbdev I/O helpers

Set struct fb_ops and with FB_DEFAULT_IOMEM_OPS, fbdev's initializer
for I/O memory. Sets the callbacks to the cfb_ and fb_io_ functions.
Select the correct modules with Kconfig's FB_IOMEM_HELPERS token.

The macro and token set the currently selected values, so there is
no functional change.

v3:
	* use _IOMEM_ in commit message
v2:
	* updated to use _IOMEM_ tokens
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Helge Deller <deller@gmx.de>
Cc: Timur Tabi <timur@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230803184034.6456-12-tzimmermann@suse.de

drivers/video/fbdev/Kconfig

@@ -1661,10 +1661,8 @@ config PXA3XX_GCU
 config FB_FSL_DIU
 	tristate "Freescale DIU framebuffer support"
 	depends on FB && FSL_SOC
+	select FB_IOMEM_HELPERS
 	select FB_MODE_HELPERS
-	select FB_CFB_FILLRECT
-	select FB_CFB_COPYAREA
-	select FB_CFB_IMAGEBLIT
 	select PPC_LIB_RHEAP
 	help
 	  Framebuffer driver for the Freescale SoC DIU

drivers/video/fbdev/fsl-diu-fb.c

@@ -1451,13 +1451,11 @@ static int fsl_diu_release(struct fb_info *info, int user)
 
 static const struct fb_ops fsl_diu_ops = {
 	.owner = THIS_MODULE,
+	FB_DEFAULT_IOMEM_OPS,
 	.fb_check_var = fsl_diu_check_var,
 	.fb_set_par = fsl_diu_set_par,
 	.fb_setcolreg = fsl_diu_setcolreg,
 	.fb_pan_display = fsl_diu_pan_display,
-	.fb_fillrect = cfb_fillrect,
-	.fb_copyarea = cfb_copyarea,
-	.fb_imageblit = cfb_imageblit,
 	.fb_ioctl = fsl_diu_ioctl,
 	.fb_open = fsl_diu_open,
 	.fb_release = fsl_diu_release,