Fix maes and lr_scheduler division by zero
# Bugfix
- Fix maes num steps < 2, force to be >= 2 for now until auto tuning is ready
- Fix lr scheduler division by 0 error if num_workers is 0
- Fix dataloader injection when provided base dictionary and not DictConfig
- Fix DALI on CPU

Signed-off-by: smajumdar <titu1994@gmail.com>