Do not detect "~/.steam/steam" as another Steam installation on Linux

[Tiagoquix]

trafficstars

~/.steam/steam is detected as one of the "multiple installations" alongside with ~/.local/share/Steam/.

~/.steam/steam is a link to ~/.local/share/Steam/.

It should not be detected as a multiple Steam install.

I'm not sure if the program tries to detect ~/.steam/root, but it is also a link to ~/.local/share/Steam/.

[WinterPhoenix]

~/.steam/steam is a legacy install location, so Steam puts symlink there even if it's installed in the new location. We should probably just be resolving symlinks so it doesn't detect them separately

[WinterPhoenix]

Should be fixed in the latest release.