If attempting to flash the firmware with a blob of size 0,
the entire write loop is skipped and the uninitialized err
is returned. Fix by setting to 0 first.
Fixes: 773bda964921 ("ptp: ocp: Expose various resources on the timecard.") Signed-off-by: Jonathan Lemon <jonathan.lemon@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>