perf maps: Mark ksymbol DSOs with kernel type

We add ksymbol map into machine->kmaps, so it needs to be created as
'struct kmap', which is dependent on its dso having kernel type.

Reported-by: Ravi Bangoria <[e-mail]>
Signed-off-by: Jiri Olsa <[e-mail]>
Tested-by: Ravi Bangoria <[e-mail]>
Tested-by: Kim Phillips <[e-mail]>
Cc: Alexander Shishkin <[e-mail]>
Cc: Michael Petlan <[e-mail]>
Cc: Namhyung Kim <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Link: http://lore.kernel.org/lkml/20200210200847.GA36715@krava
Signed-off-by: Arnaldo Carvalho de Melo <[e-mail]>

tools/perf/util/machine.c

···
 	struct map *map = maps__find(&machine->kmaps, event->ksymbol.addr);
 
 	if (!map) {
-		map = dso__new_map(event->ksymbol.name);
-		if (!map)
+		struct dso *dso = dso__new(event->ksymbol.name);
+
+		if (dso) {
+			dso->kernel = DSO_TYPE_KERNEL;
+			map = map__new2(0, dso);
+		}
+
+		if (!dso || !map) {
+			dso__put(dso);
 			return -ENOMEM;
+		}
 
 		map->start = event->ksymbol.addr;
 		map->end = map->start + event->ksymbol.len;