drm/radeon|amgpu: Make fbdev emulation optional

Seems to at least compile fine, only change needed was to use
the fb_set_suspend helper.

Cc: [e-mail]
Reviewed-by: Alex Deucher <[e-mail]>
Signed-off-by: Daniel Vetter <[e-mail]>
Link: http://patchwork.freedesktop.org/patch/msgid/[e-mail]

drivers/gpu/drm/Kconfig

···
 config DRM_RADEON
 	tristate "ATI Radeon"
 	depends on DRM && PCI
-	select FB_CFB_FILLRECT
-	select FB_CFB_COPYAREA
-	select FB_CFB_IMAGEBLIT
 	select FW_LOADER
         select DRM_KMS_HELPER
-	select DRM_KMS_FB_HELPER
         select DRM_TTM
 	select POWER_SUPPLY
 	select HWMON
···
 config DRM_AMDGPU
 	tristate "AMD GPU"
 	depends on DRM && PCI
-	select FB_CFB_FILLRECT
-	select FB_CFB_COPYAREA
-	select FB_CFB_IMAGEBLIT
 	select FW_LOADER
         select DRM_KMS_HELPER
-	select DRM_KMS_FB_HELPER
         select DRM_TTM
 	select POWER_SUPPLY
 	select HWMON

drivers/gpu/drm/radeon/radeon_fb.c

···
 void radeon_fbdev_set_suspend(struct radeon_device *rdev, int state)
 {
 	if (rdev->mode_info.rfbdev)
-		fb_set_suspend(rdev->mode_info.rfbdev->helper.fbdev, state);
+		drm_fb_helper_set_suspend(&rdev->mode_info.rfbdev->helper, state);
 }
 
 bool radeon_fbdev_robj_is_fb(struct radeon_device *rdev, struct radeon_bo *robj)