RTLA supports building without BPF libraries, but a recent change
added a libbpf.h include outside of the BPF protection which caused
build failures when libbpf was not installed.
* tag 'trace-rtla-v7.0-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
rtla: Fix build without libbpf header