[libnftnl PATCH] ruleset: deconstify _get interface

[Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com>]

Having this interface returning a const pointer makes very hard to
modificate the content of a chain contained in a nft_ruleset.

Signed-off-by: Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com>
---

Note: I ignore how this affects the current, already released API.

 include/libnftnl/ruleset.h |    2 +-
 src/ruleset.c              |    2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/libnftnl/ruleset.h b/include/libnftnl/ruleset.h
index 6f89110..1a3e22f 100644
--- a/include/libnftnl/ruleset.h
+++ b/include/libnftnl/ruleset.h
@@ -28,7 +28,7 @@ enum {
 bool nft_ruleset_attr_is_set(const struct nft_ruleset *r, uint16_t attr);
 void nft_ruleset_attr_unset(struct nft_ruleset *r, uint16_t attr);
 void nft_ruleset_attr_set(struct nft_ruleset *r, uint16_t attr, void *data);
-const void *nft_ruleset_attr_get(const struct nft_ruleset *r, uint16_t attr);
+void *nft_ruleset_attr_get(const struct nft_ruleset *r, uint16_t attr);
 
 int nft_ruleset_parse(struct nft_ruleset *rs, enum nft_parse_type type,
 		      const char *data, struct nft_parse_err *err);
diff --git a/src/ruleset.c b/src/ruleset.c
index 4cfeee6..6bb7582 100644
--- a/src/ruleset.c
+++ b/src/ruleset.c
@@ -111,7 +111,7 @@ void nft_ruleset_attr_set(struct nft_ruleset *r, uint16_t attr, void *data)
 }
 EXPORT_SYMBOL(nft_ruleset_attr_set);
 
-const void *nft_ruleset_attr_get(const struct nft_ruleset *r, uint16_t attr)
+void *nft_ruleset_attr_get(const struct nft_ruleset *r, uint16_t attr)
 {
 	if (!(r->flags & (1 << attr)))
 		return NULL;