drm/radeon: Drop drm_gem_prime_import

They're the default.

Aside: Would be really nice to switch the others over to
drm_gem_object_funcs.
Reviewed-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Emil Velikov <emil.velikov@collabora.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190614203615.12639-36-daniel.vetter@ffwll.ch

drivers/gpu/drm/radeon/radeon_drv.c

@@ -564,7 +564,6 @@ static struct drm_driver kms_driver = {
 	.prime_handle_to_fd = drm_gem_prime_handle_to_fd,
 	.prime_fd_to_handle = drm_gem_prime_fd_to_handle,
 	.gem_prime_export = radeon_gem_prime_export,
-	.gem_prime_import = drm_gem_prime_import,
 	.gem_prime_pin = radeon_gem_prime_pin,
 	.gem_prime_unpin = radeon_gem_prime_unpin,
 	.gem_prime_res_obj = radeon_gem_prime_res_obj,