The linux kernel git commit 6dfeff09d5ad33190 removes the include for
<uapi/linux/wait.h> from <linux/wait.h>. The kernel has had
<uapi/linux/wait.h> header for over a dozen years (kernel git commit 607ca46e97a1b65) and systemtap should just use that directly. The
downside of this change is that systemtap will require a Linux 3.7 or
newer kernel.