Revert bevyengine#331 (bevyengine#2502)

# Objective

@TomBebb (other account being @TomBebbington ) proved unreachable for bevyengine#2373, so we need to revert their changes for the relicense.

## Solution

Revert their changes. This is only linux distro docs, so it's not critical code.

If someone else wants to test `bevy` on solus to work out the set of packages independently, then we'll probably accept a PR to add these. One suggestsion would be to consider the packages required on other systems, since there is likely to be some overlap.

## Alternatives

Link to this old version in the `linux_dependencies.md` file.

docs/linux_dependencies.md

@@ -49,12 +49,6 @@ sudo dnf install alsa-lib-devel.x86_64
 sudo pacman -S libx11 pkgconf alsa-lib
 ```
 
-## Solus
-
-```bash
-sudo eopkg install pkg-config libx11-devel g++ alsa-lib-devel
-```
-
 ## Void
 
 ```bash