config: enable CONFIG_EROFS_FS

[valpackett]

EROFS is used by e.g. NixOS's etc overlay, and other distribution tools. Seems to have no size impact on x86_64 (19138272 before and after).

---

I'm not sure why (fitting into some kind of padding inside of the image?? 0.o) but size didn't increase:

❯ strings /nix/store/47md2yyhvpn2a8y7rjbzagvr757wqwgb-libkrunfw-5.0.0/lib/libkrunfw.so.5.0.0 | rg erof | wc -l
3
❯ strings /nix/store/qgf7cbvkr82rdmqyvkd6jndz8gcp25gv-libkrunfw-5.0.0/lib/libkrunfw.so.5.0.0 | rg erof | wc -l
43
❯ ls -la /nix/store/47md2yyhvpn2a8y7rjbzagvr757wqwgb-libkrunfw-5.0.0/lib/libkrunfw.so.5.0.0 /nix/store/qgf7cbvkr82rdmqyvkd6jndz8gcp25gv-libkrunfw-5.0.0/lib/libkrunfw.so.5.0.0
-r-xr-xr-x 1 root root 19138272 Dec 31  1969 /nix/store/47md2yyhvpn2a8y7rjbzagvr757wqwgb-libkrunfw-5.0.0/lib/libkrunfw.so.5.0.0
-r-xr-xr-x 1 root root 19138272 Dec 31  1969 /nix/store/qgf7cbvkr82rdmqyvkd6jndz8gcp25gv-libkrunfw-5.0.0/lib/libkrunfw.so.5.0.0

[tylerfanelli]

LGTM.