build: disable more warnings for clang
build: disable more warnings for clang

We should fix the source and re-enable the warnings, but this will do for
now.

duarten/scylla,scylladb/scylla,scylladb/scylla,avikivity/scylla,scylladb/scylla,scylladb/scylla,duarten/scylla,duarten/scylla,avikivity/scylla,avikivity/scylla