perf symbols: Add the path to vmlinux.debug

Currently when debuginfo is separated to vmlinux.debug, it's contents
get ignored. Let's change that and add it to the vmlinux_path list.
Signed-off-by: Ekaterina Tumanova <tumanova@linux.vnet.ibm.com>
Acked-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1448469166-61363-3-git-send-email-tumanova@linux.vnet.ibm.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/symbol.c

@@ -1869,7 +1869,8 @@ static const char * const vmlinux_paths_upd[] = {
 	"/boot/vmlinux-%s",
 	"/usr/lib/debug/boot/vmlinux-%s",
 	"/lib/modules/%s/build/vmlinux",
-	"/usr/lib/debug/lib/modules/%s/vmlinux"
+	"/usr/lib/debug/lib/modules/%s/vmlinux",
+	"/usr/lib/debug/boot/vmlinux-%s.debug"
 };
 
 static int vmlinux_path__add(const char *new_entry)