Add Transmission lines and IBIS simulation symbols

This is to be merged before v7 release.

I opened this MR to keep track of the addition in the dev branch.

This does the following:

• Adds differential voltage probe symbol as shown !3677 (merged)

( Also a spice model )

• Adds transmission line and IBIS device/driver symbols as shown !3395 (merged)

( Also sets some initial values in some fields )

• Changes two simulation related diodes with a symbol copied as it currently is in the device library

• And lastly one final save touching only the two simulation libraries with current KiCad v7-rc as described in the commit messages.

This is to get merged without squashing option.