Serial over LAN (SoL) layout is broken

[Kostr]

Serial over LAN (SoL) element takes too little window space (opposed to KVM for example):

If it is an intention, everything looks especially broken, when SoL is opened in a new window:

Besides it is too small and aligned left, you can see, that terminal doesn't use full window space for its output

[gtmills]

This was on the mailing list here: https://lists.ozlabs.org/pipermail/openbmc/2020-November/023891.html

[Kostr]

Some screenshots for the proposed commit (https://gerrit.openbmc-project.xyz/c/openbmc/phosphor-webui/+/38036)

I didn't touched fixed height of the terminal in the main SoL tab. The terminal still takes 25em in height:

But I've added responsiveness, so the terminal content resizes when the window gets shorter than a default terminal width:

The main changes are in the separate SoL window. It opens like before in 640x550, but now:
-XTERM always use full terminal viewport space
-terminal viewport width always equals window space width
-terminal viewport automatically resizes on window size changes
-terminal content automatically resizes with the viewport changes

As SOL UI is resposive now, this commit also removes fixed size configurations for the SOL terminal via JSON 'customConsoleDisplaySize' variable. It is worth noting that in reality it wasn't used by anybody.

Also I want to note, that I'm not a professional UI designer, I did this change for myself, and added this commit just in case it would be useful for anybody else in the OpenBMC community.