benchmarks/stress-ng: fix build on CURRENT,

In CURRENT, the initial configuration detects now support for the
scheduler affinity, enabling the build of an additional stressor.
In this stressor, the CPU_OR macro has 3 arguments (Linux implementation),
while on FreeBSD it has only 2 arguments.

This patch provides the fix

No bumprevision is provided, because it's only fixing CURRENT where the
build was failing.

benchmarks/stress-ng/files/patch-stress-tlb-shootdown.c

@@ -0,0 +1,11 @@
+--- stress-tlb-shootdown.c.orig	2021-12-28 15:45:13 UTC
++++ stress-tlb-shootdown.c
+@@ -64,7 +64,7 @@ static int stress_tlb_shootdown(const stress_args_t *a
+ 		const int32_t max_cpus = stress_get_processors_configured();
+
+ 		CPU_ZERO(&proc_mask);
+-		CPU_OR(&proc_mask, &proc_mask_initial, &proc_mask);
++		CPU_OR(&proc_mask, &proc_mask_initial);
+
+ 		tlb_procs = max_cpus;
+ 		if (tlb_procs > MAX_TLB_PROCS)