Add shebang line to dut_control.py

All python files that are expected to be executed should have this.
If you don't, you get something like this if you try to run:

$ ./servo/dut_control.py --help
./servo/dut_control.py: line 5: Client to control DUT hardware connected to servo debug board
: command not found

BUG=none
TEST=Ran ./servo/dut_control.py --help and saw no errors.

Change-Id: I7ab3ce6e5a6d3de2f42ec49dbc56c5cb3e9fc94c
Reviewed-on: http://gerrit.chromium.org/gerrit/5147
Reviewed-by: Todd Broch <tbroch@chromium.org>
Tested-by: Doug Anderson <dianders@chromium.org>
1 file changed