drm/vram-helpers: Create DRM_GEM_VRAM_PLANE_HELPER_FUNCS

Like we have for the shadow helpers too, and roll it out to drivers.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Tian Tao <tiantao6@hisilicon.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Tian Tao <tiantao6@hisilicon.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210622165511.3169559-11-daniel.vetter@ffwll.ch