Fix computing bytes fields (memory and disk space)
Fix computing bytes fields (memory and disk space)

It seems that all new RouterOS versions are reporting those fields
as bytes, so remove the multipliers introduced in 460236c.

Successfully tested on the following RouterOS versions:
- 6.38.5 (stable)
- 6.42.1 (stable)
- 6.42.3 (stable)
- 6.43rc42 (testing)

The revert is partial (not affecting CPU frequency).
Closes #6

octo/librouteros,octo/librouteros