fbdev/hyperv_fb: deprecate this in favor of Hyper-V DRM driver

The Hyper-V DRM driver is available since kernel version 5.14 and it
provides full KMS support and fbdev emulation via the DRM fbdev helpers.
Deprecate this driver in favor of Hyper-V DRM driver.

Signed-off-by: Prasanna Kumar T S M <ptsm@linux.microsoft.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Michael Kelley <mhklinux@outlook.com>
Reviewed-by: Saurabh Sengar <ssengar@linux.microsoft.com>
Signed-off-by: Wei Liu <wei.liu@kernel.org>

Author: Prasanna Kumar T S M

drivers/video/fbdev/Kconfig

@@ -1773,13 +1773,16 @@ config FB_BROADSHEET
 	  a bridge adapter.
 
 config FB_HYPERV
-	tristate "Microsoft Hyper-V Synthetic Video support"
+	tristate "Microsoft Hyper-V Synthetic Video support (DEPRECATED)"
 	depends on FB && HYPERV_VMBUS
 	select DMA_CMA if HAVE_DMA_CONTIGUOUS && CMA
 	select FB_IOMEM_HELPERS_DEFERRED
 	help
 	  This framebuffer driver supports Microsoft Hyper-V Synthetic Video.
 
+	  This driver is deprecated, please use the Hyper-V DRM driver at
+	  drivers/gpu/drm/hyperv (CONFIG_DRM_HYPERV) instead.
+
 config FB_SIMPLE
 	tristate "Simple framebuffer support"
 	depends on FB

drivers/video/fbdev/hyperv_fb.c

@@ -1357,6 +1357,8 @@ static int __init hvfb_drv_init(void)
 {
 	int ret;
 
+	pr_warn("Deprecated: use Hyper-V DRM driver instead\n");
+
 	if (fb_modesetting_disabled("hyper_fb"))
 		return -ENODEV;