fbdev/imxfb: 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: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Pengutronix Kernel Team <kernel@pengutronix.de>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: NXP Linux Team <linux-imx@nxp.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230803184034.6456-21-tzimmermann@suse.de

drivers/video/fbdev/Kconfig

@@ -175,9 +175,7 @@ config FB_IMX
 	depends on FB && HAVE_CLK && HAS_IOMEM
 	depends on ARCH_MXC || COMPILE_TEST
 	select LCD_CLASS_DEVICE
-	select FB_CFB_FILLRECT
-	select FB_CFB_COPYAREA
-	select FB_CFB_IMAGEBLIT
+	select FB_IOMEM_HELPERS
 	select FB_MODE_HELPERS
 	select VIDEOMODE_HELPERS
 

drivers/video/fbdev/imxfb.c

@@ -580,12 +580,10 @@ static int imxfb_blank(int blank, struct fb_info *info)
 
 static const struct fb_ops imxfb_ops = {
 	.owner		= THIS_MODULE,
+	FB_DEFAULT_IOMEM_OPS,
 	.fb_check_var	= imxfb_check_var,
 	.fb_set_par	= imxfb_set_par,
 	.fb_setcolreg	= imxfb_setcolreg,
-	.fb_fillrect	= cfb_fillrect,
-	.fb_copyarea	= cfb_copyarea,
-	.fb_imageblit	= cfb_imageblit,
 	.fb_blank	= imxfb_blank,
 };