[Mellanox][sonic-bfb-installer] Adding Debug print messages

[gpunathilell]

Why I did it

Addition of debug print messages to keep the SSH connection alive and to add per-dpu configuration capability with separate config files

Work item tracking

• Microsoft ADO (number only):

How I did it

How to verify it

sonic-bfb-installer.sh -r all -c a.conf,b.conf,c.conf,d.conf sets the configuration individually for each dpus
The rshim devices are sorted before we apply the configuration
a.conf for rshim0, b.conf for the second and so on
We can also see debug pring messages during installation to keep the ssh connection alive

Which release branch to backport (provide reason below if selected)

• 201811
• 201911
• 202006
• 202012
• 202106
• 202111
• 202205
• 202211
• 202305

Tested branch (Please provide the tested image version)

Description for the changelog

Link to config_db schema for YANG module changes

A picture of a cute animal (not mandatory but encouraged)