perf symbols: Fix inverted logic for showing kallsyms as the source of symbols

Only if we parsed /proc/kallsyms (or a copy found in the buildid
cache) we should set the dso long name to "[kernel.kallsyms]".
Reported-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1264178102-4203-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

tools/perf/util/symbol.c

@@ -1671,7 +1671,7 @@ static int dso__load_kernel_sym(struct dso *self, struct map *map,
 out_try_fixup:
 	if (err > 0) {
 out_fixup:
-		if (kallsyms_filename == NULL)
+		if (kallsyms_filename != NULL)
 			dso__set_long_name(self, strdup("[kernel.kallsyms]"));
 		map__fixup_start(map);
 		map__fixup_end(map);