Rework IOL interface mapping

[kaelemc]

This PR reworks IOL interface handling, and more importantly allows for ethX interface naming -- which is important for c9s users.

Some artifacts from when IOL was a VRNode were cleaned up/removed and I hope the new variable names are more descriptive for the different regexp's.

A new error message will also be shown if the management interface is trying to be used in the topology (eth0, e0/0 or Ethernet0/0)

Let me know if anything is wrong, needs to be changed etc.

[codecov]

Codecov Report

Attention: Patch coverage is 63.63636% with 8 lines in your changes missing coverage. Please review.

Project coverage is 51.88%. Comparing base (a75e770) to head (b50a7d5).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
nodes/iol/iol.go	63.63%	6 Missing and 2 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2400      +/-   ##
==========================================
- Coverage   51.89%   51.88%   -0.01%     
==========================================
  Files         172      172              
  Lines       17316    17321       +5     
==========================================
+ Hits         8986     8987       +1     
- Misses       7386     7389       +3     
- Partials      944      945       +1     

Files with missing lines	Coverage Δ
nodes/iol/iol.go	81.03% <63.63%> (-1.35%)	⬇️