net, tests, hot-plug: Avoid redundant VMI interface lookup - #5578

pytest-check-arm64: OK ✔ in 9 minutes 37.22 seconds
pytest-check-s390x: OK ✔ in 9 minutes 37.15 seconds
utilities-unittests: OK ✔ in 9 minutes 44.23 seconds
pytest-check-multiarch: OK ✔ in 9 minutes 55.05 seconds
unused-code: OK ✔ in 12 minutes 33.46 seconds
  pytest-check-x86: OK (992.27=setup[266.75]+cmd[312.00,10.93,6.87,16.88,11.74,14.94,7.42,14.81,210.67,119.26] seconds)
  pytest-check-arm64: OK (577.22=setup[338.46]+cmd[238.76] seconds)
  pytest-check-s390x: OK (577.15=setup[349.72]+cmd[227.43] seconds)
  pytest-check-multiarch: OK (595.05=setup[338.16]+cmd[238.50,11.61,6.78] seconds)
  unused-code: OK (753.46=setup[686.37]+cmd[67.09] seconds)
  utilities-unittests: OK (584.23=setup[253.46]+cmd[330.68,0.08] seconds)
  congratulations :) (993.86 seconds)