perf tools: Provide stub for missing pthread_attr_setaffinity_np

uClibc Linuxthreads.old doesn't support the pthread_attr_setaffinity_np()
functioo:

   ----------------->8-----------------------
  CC       bench/futex-hash.o
  CC       bench/futex-wake.o
bench/futex-hash.c: In function 'bench_futex_hash':
bench/futex-hash.c:161:3: error: implicit declaration of function
'pthread_attr_setaffinity_np' [-Werror=implicit-function-declaration]
   ret = pthread_attr_setaffinity_np(&thread_attr, sizeof(cpu_set_t),
&cpu);
   ^
bench/futex-hash.c:161:3: error: nested extern declaration of
'pthread_attr_setaffinity_np' [-Werror=nested-externs]
   ----------------->8-----------------------

So introduce a test to check that and if not available provide a stub.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexey Brodkin <Alexey.Brodkin@synopsys.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1421156604-30603-6-git-send-email-vgupta@synopsys.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/bench/futex.h b/tools/perf/bench/futex.h
index 71f2844..7ed22ff 100644
--- a/tools/perf/bench/futex.h
+++ b/tools/perf/bench/futex.h
@@ -68,4 +68,17 @@
 		 val, opflags);
 }
 
+#ifndef HAVE_PTHREAD_ATTR_SETAFFINITY_NP
+#include <pthread.h>
+static inline int pthread_attr_setaffinity_np(pthread_attr_t *attr,
+					      size_t cpusetsize,
+					      cpu_set_t *cpuset)
+{
+	attr = attr;
+	cpusetsize = cpusetsize;
+	cpuset = cpuset;
+	return 0;
+}
+#endif
+
 #endif /* _FUTEX_H */