perf probe: Fix use of kernel image path given by 'k' option

Users were not being able to have the explicitely specified vmlinux
pathname used, instead a search on the vmlinux path was always being
made.

Reported-by: Francis Moreau <francis.moro@gmail.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: 2nddept-manager@sdl.hitachi.co.jp
Cc: Francis Moreau <francis.moro@gmail.com>
Cc: Franck Bui-Huu <vagabon.xyz@gmail.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
LPU-Reference: <m3hbelydz8.fsf_-_@gmail.com>
Signed-off-by: Franck Bui-Huu <fbuihuu@gmail.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index d628c8d..439ab94 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -1780,8 +1780,8 @@
 	return -1;
 }
 
-static int dso__load_vmlinux(struct dso *self, struct map *map,
-			     const char *vmlinux, symbol_filter_t filter)
+int dso__load_vmlinux(struct dso *self, struct map *map,
+		      const char *vmlinux, symbol_filter_t filter)
 {
 	int err = -1, fd;