Fixed Python 3 bug in Flash handling of flash algo debug mode.
Fixed Python 3 bug in Flash handling of flash algo debug mode.

flit/pyOCD,flit/pyOCD,mesheven/pyOCD,mbedmicro/pyOCD,mbedmicro/pyOCD,pyocd/pyOCD,mesheven/pyOCD,pyocd/pyOCD,mesheven/pyOCD,mbedmicro/pyOCD