l2md: use correct path in error msg when config cannot be opened

It's the path variable and not tmp, so use the correct one.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
diff --git a/config.c b/config.c
index 3abf25b..dd277cb 100644
--- a/config.c
+++ b/config.c
@@ -215,7 +215,7 @@
 	slprintf(path, sizeof(path), "%s/.l2mdconfig", homedir);
 	fp = fopen(path, "r");
 	if (!fp)
-		panic("Cannot open config %s: %s\n", tmp, strerror(errno));
+		panic("Cannot open config %s: %s\n", path, strerror(errno));