perf: Apply patch for offline kernels

As per https://lkml.org/lkml/2017/7/13/314, perf is broken in 4.9.36 and 4.9.37
Patches in this commit are taken from
https://git.kernel.org/pub/scm/linux/kernel/git/stable/stable-queue.git/commit/?id=39f4f2c018bd831c325e11983f8893caf72fd9eb

This will allow perf to build again and should be included in a future 4.9.x release,
allowing the custom patching to be removed again