runners: canopen: poll for flash ready

Poll the flash status instead of just reading the flash status once. Add
support for controlling the number of SDO retries and the SDO timeouts.

These changes allows for greater control of the CANopen program
download, which is especially useful on noisy or congested CAN networks
and on devices with slower flash access.

Fixes: #39409

Signed-off-by: Klaus H. Sorensen <khso@vestas.com>
Signed-off-by: Henrik Brix Andersen <hebad@vestas.com>