fbdev/au1100fb: Initialize fb_ops to fbdev I/O-memory helpers

Initialize the instance of struct fb_ops with fbdev initializer
macros for framebuffers in I/O address space. Set the read/write,
draw and mmap callbacks to the correct implementation and avoid
implicit defaults. Also select the necessary I/O helpers in Kconfig.

Fbdev drivers sometimes rely on the callbacks being NULL for a
default implementation to be invoked; hence requiring the I/O
helpers to be built in any case. Setting all callbacks in all
drivers explicitly will allow to make the I/O helpers optional.
This benefits systems that do not use these functions.

No functional changes.

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

drivers/video/fbdev/Kconfig

···
 config FB_AU1100
 	bool "Au1100 LCD Driver"
 	depends on (FB = y) && MIPS_ALCHEMY
-	select FB_CFB_FILLRECT
-	select FB_CFB_COPYAREA
-	select FB_CFB_IMAGEBLIT
+	select FB_IOMEM_HELPERS
 	help
 	  This is the framebuffer driver for the AMD Au1100 SOC.  It can drive
 	  various panels and CRTs by passing in kernel cmd line option

drivers/video/fbdev/au1100fb.c

···
 			fbdev->fb_len);
 }
 
-static const struct fb_ops au1100fb_ops =
-{
+static const struct fb_ops au1100fb_ops = {
 	.owner			= THIS_MODULE,
+	__FB_DEFAULT_IOMEM_OPS_RDWR,
 	.fb_setcolreg		= au1100fb_fb_setcolreg,
 	.fb_blank		= au1100fb_fb_blank,
 	.fb_pan_display		= au1100fb_fb_pan_display,
-	.fb_fillrect		= cfb_fillrect,
-	.fb_copyarea		= cfb_copyarea,
-	.fb_imageblit		= cfb_imageblit,
+	__FB_DEFAULT_IOMEM_OPS_DRAW,
 	.fb_mmap		= au1100fb_fb_mmap,
 };