drivers/kitprog: workaround KitProg firmware bug of missing ZLP
KitProg firmware does not send a zero length packet at the end of the bulk-in
transmission of a length divisible by a bulk packet size. This is inconsistent
with the USB specification and results in jtag_libusb_bulk_read()
waits forever when a transmission of specific size is received.
Limit bulk read size to expected number of bytes for problematic tranfer sizes.
Use 1 second timeout as the last resort.