Clang toolchain does not work on Ubuntu 24.04

[jwnrt]

Clang is dynamically linked against libncursesw.so.5/libtinfo.so.5. We usually statically link, but for some reason dynamic linking is explicitly allowed here:

lowrisc-toolchains/check-tarball.sh

Line 86 in 482ead1

export LIBCHECK_ALLOW='libstdc\+\+|libtinfo|libncursesw|libz'

Ubuntu 24.04 removed version 5 of libncurses and libtinfo, there's only version 6 now.

CC @AlexJones0 who is trying to use Ubuntu 24.04