Make the option structures const.

Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
diff --git a/extensions/libip6t_condition.c b/extensions/libip6t_condition.c
index 633eef1..40d0522 100644
--- a/extensions/libip6t_condition.c
+++ b/extensions/libip6t_condition.c
@@ -19,7 +19,7 @@
 }
 
 
-static struct option opts[] = {
+static const struct option opts[] = {
 	{ .name = "condition", .has_arg = 1, .flag = 0, .val = 'X' },
 	{ .name = 0 }
 };