Decouple baud rate and device file descriptors configuration program options

[Deniz-Eren]

Decouple baud rate and device RX/TX file descriptor configuration program options.

• Option -d used for bus-off recovery delay timer duration has been modified to be -r.
• New option -b used to configure the baud-rate of devices.
• Improvements to program option validation checks
  • Added checks for -u and -b id=# suboptions to ensure user selections are consistent with devices available.
  • Modified all program option checks to be reported to the user before exiting with failure.