[PATCH libnetfilter_conntrack] src: Make the library compile under clang

[Kevin Cernekee <cernekee@chromium.org>]

clang treats "char buffer[size]" inside a union as VLAIS unless |size|
is const:

src/conntrack/api.c:992:8: error: fields must have a constant size: 'variable length array in structure' extension will never be supported
                char buffer[size];
                     ^

Signed-off-by: Kevin Cernekee <cernekee@chromium.org>
---
 src/conntrack/api.c | 4 ++--
 src/expect/api.c    | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/conntrack/api.c b/src/conntrack/api.c
index e4d4acc312bb..bed2e42c8f43 100644
--- a/src/conntrack/api.c
+++ b/src/conntrack/api.c
@@ -955,7 +955,7 @@ int nfct_query(struct nfct_handle *h,
 	       const enum nf_conntrack_query qt,
 	       const void *data)
 {
-	size_t size = 4096;	/* enough for now */
+	const size_t size = 4096;	/* enough for now */
 	union {
 		char buffer[size];
 		struct nfnlhdr req;
@@ -987,7 +987,7 @@ int nfct_send(struct nfct_handle *h,
 	      const enum nf_conntrack_query qt,
 	      const void *data)
 {
-	size_t size = 4096;	/* enough for now */
+	const size_t size = 4096;	/* enough for now */
 	union {
 		char buffer[size];
 		struct nfnlhdr req;
diff --git a/src/expect/api.c b/src/expect/api.c
index 8ff20e2821e3..3f1763038ede 100644
--- a/src/expect/api.c
+++ b/src/expect/api.c
@@ -669,7 +669,7 @@ int nfexp_query(struct nfct_handle *h,
 	        const enum nf_conntrack_query qt,
 	        const void *data)
 {
-	size_t size = 4096;	/* enough for now */
+	const size_t size = 4096;	/* enough for now */
 	union {
 		char buffer[size];
 		struct nfnlhdr req;
@@ -701,7 +701,7 @@ int nfexp_send(struct nfct_handle *h,
 	       const enum nf_conntrack_query qt,
 	       const void *data)
 {
-	size_t size = 4096;	/* enough for now */
+	const size_t size = 4096;	/* enough for now */
 	union {
 		char buffer[size];
 		struct nfnlhdr req;
-- 
2.8.0.rc3.226.g39d4020