lf_ftp.py : Added robot - bandsteering functionality.

Verified CLI : python3 lf_ftp.py --ssid Netgear-5g --passwd sharedsecret --file_sizes 10MB --mgr 192.168.207.78 --traffic_duration 1m --security wpa2 --directions Download --clients_type Real --ap_name Netgear --bands 5G --upstream_port eth1 --robot_test --robot_ip 192.168.204.101 --coordinate 3,4 --do_bandsteering --cycles 1 --bssids 04:f0:21:94:dc:46

Signed-off-by: Sidartha-CT <neelapu.sidartha@candelatech.com>

Author: Sidartha-CT