perf test code-reading: Fix perf_env setup for PTI entry trampolines

The "Object code reading" test will not create maps for the PTI entry
trampolines unless the machine environment exists to show that the arch is
x86_64.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Reported-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1528183800-21577-1-git-send-email-adrian.hunter@intel.com
[ split from a larger patch ]
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/tests/code-reading.c

@@ -560,6 +560,7 @@ static int do_test_code_reading(bool try_kcore)
 	pid = getpid();
 
 	machine = machine__new_host();
+	machine->env = &perf_env;
 
 	ret = machine__create_kernel_maps(machine);
 	if (ret < 0) {