drm: Shift wrap bug in create_in_format_blob()

"plane->format_count" can go up to 64.  (It's capped in
drm_universal_plane_init().)  So we should be using ULL type instead of
int here to prevent shift wrapping.

Fixes: db1689aa ("drm: Create a format/modifier blob")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20170809111906.4rv3hzritctfktv3@mwanda