linuxPackages.bcc: 0.8.0 -> 0.9.0

Requires a minor tweak to the deadlock detector patch (the file was
renamed in the upstream repo).

bcc now also wants a copy of libbpf, which it doesn't have in the source
release tarball. Clone a copy from GiHub that's synchronized with the
release, and put it in place.

Tested on Linux 5.1 (with bpftrace as well).

Signed-off-by: Austin Seipp <aseipp@pobox.com>