drm/starfive: set FOP_UNSIGNED_OFFSET in starfive_drm_driver_fops
Created by: andreas-schwab
This fixes the error from drm_open:
[ +0.000020] [ C1] WARNING: CPU: 1 PID: 1110 at drivers/gpu/drm/drm_file.c
Signed-off-by: Andreas Schwab schwab@suse.de