Support multiple dediprog devices under linux

[muthuselvamr]

This issue is created to check if the enhancement made to support multiple dediprog device support under linux environment.

#2

Currently, dpcmd provides environment variables DPCMD_USB_BUSNUM and DPCMD_USB_DEVNUM to identify the dediprog device when multiple dediprog devices are connected.

But We face a problem that when the linux host where dediprog devices are connected are disturbed or restarted, the USB BUS DEVICe number changed for particular dediprog device. It is not fixed.

If possible please implement, identifying dediprog device using Serial Number instead of BUS DEV numbers, this is implemented in em100 linux software, similar kind of implementation would be helpful here.