With the update of RHEL7.3 to RHEL7.4 the perf sub-system
of the stable linux-4.4.X branch fails to build.

tools/perf/bench/futex.h:36:10: error: 'SYS_futex' undeclared
tools/perf/tests/mmap-thread-lookup.c:42:20: error: 'SYS_gettid' undeclared

Fix by inserting two conditional hash-defines.

Signed-off-by: Alan Bartlett <ajb@elrepo.org>
Cc: Akemi Yagi <toracat@elrepo.org>
Cc: Philip J Perry <phil@elrepo.org>

diff -Npru a/tools/perf/bench/futex.h b/tools/perf/bench/futex.h
--- a/tools/perf/bench/futex.h	2017-11-02 04:40:50.000000000 -0400
+++ b/tools/perf/bench/futex.h	2017-11-05 19:59:35.063971553 -0500
@@ -12,6 +12,10 @@
 #include <sys/types.h>
 #include <linux/futex.h>
 
+#ifndef SYS_futex
+#define SYS_futex __NR_futex
+#endif
+
 /**
  * futex() - SYS_futex syscall wrapper
  * @uaddr:	address of first futex
diff -Npru a/tools/perf/tests/tests.h b/tools/perf/tests/tests.h
--- a/tools/perf/tests/tests.h	2017-11-02 04:40:50.000000000 -0400
+++ b/tools/perf/tests/tests.h	2017-11-05 20:00:59.702007286 -0500
@@ -1,6 +1,10 @@
 #ifndef TESTS_H
 #define TESTS_H
 
+#ifndef SYS_gettid
+#define SYS_gettid __NR_gettid
+#endif
+
 #define TEST_ASSERT_VAL(text, cond)					 \
 do {									 \
 	if (!(cond)) {							 \