perf symbols: Define EM_AARCH64 for older OSes

4886f2c added an arm-64 check, but the EM_AARCH64 macro is not
defined in older releases (e.g., RHEL6). Define if it is not defined.

Signed-off-by: David Ahern <david.ahern@oracle.com>
Cc: Victor Kamensky <victor.kamensky@linaro.org>
Link: http://lkml.kernel.org/r/1424306017-96797-1-git-send-email-david.ahern@oracle.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/symbol-elf.c

@@ -11,6 +11,11 @@
 #include <symbol/kallsyms.h>
 #include "debug.h"
 
+#ifndef EM_AARCH64
+#define EM_AARCH64	183  /* ARM 64 bit */
+#endif
+
+
 #ifdef HAVE_CPLUS_DEMANGLE_SUPPORT
 extern char *cplus_demangle(const char *, int);