selftests/powerpc: Move pick_online_cpu() up into utils.c

We want to use this in another test, so make it available at the top of
the powerpc selftests tree.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

tools/testing/selftests/powerpc/pmu/lib.c

@@ -15,32 +15,6 @@
 #include "lib.h"
 
 
-int pick_online_cpu(void)
-{
-	cpu_set_t mask;
-	int cpu;
-
-	CPU_ZERO(&mask);
-
-	if (sched_getaffinity(0, sizeof(mask), &mask)) {
-		perror("sched_getaffinity");
-		return -1;
-	}
-
-	/* We prefer a primary thread, but skip 0 */
-	for (cpu = 8; cpu < CPU_SETSIZE; cpu += 8)
-		if (CPU_ISSET(cpu, &mask))
-			return cpu;
-
-	/* Search for anything, but in reverse */
-	for (cpu = CPU_SETSIZE - 1; cpu >= 0; cpu--)
-		if (CPU_ISSET(cpu, &mask))
-			return cpu;
-
-	printf("No cpus in affinity mask?!\n");
-	return -1;
-}
-
 int bind_to_cpu(int cpu)
 {
 	cpu_set_t mask;