Don't reset the target when a serial break is received (for UDB).
Don't reset the target when a serial break is received (for UDB).

See
https://github.com/ARMmbed/DAPLink/issues/738
for more history/details.  This is a feature for DAPLink CI testing,
but a "bug" for our useage.

google/DAPLink-port,google/DAPLink-port,google/DAPLink-port,google/DAPLink-port