When compiling ebpf programs on Alpine Linux the compiler throws the following
error:

LLVM ERROR: Cannot select: 0x56049b79dcb0: ch,glue = BPFISD::CALL 0x56049a93ad60, TargetExternalSymbol:i64'__stack_chk_fail'
  0x56049b391500: i64 = TargetExternalSymbol'__stack_chk_fail'
    In function: waker

Disabling the stack protector explicitly with '-fno-stack-protector'
fixes this error.

clang version 3.8.1 (tags/RELEASE_381/final)
Target: x86_64-alpine-linux-musl
Thread model: posix
InstalledDir: /usr/bin
Signed-off-by: Rolf Neugebauer <rolf.neugebauer@docker.com>