Build fixes.

config.h

@@ -28,4 +28,5 @@
 #define uthash_malloc(sz) mosquitto__malloc(sz)
 #define uthash_free(ptr,sz) mosquitto__free(ptr)
 
+#define _BSD_SOURCE
 #define _POSIX_C_SOURCE 200809L

src/websockets.c

@@ -29,6 +29,8 @@ POSSIBILITY OF SUCH DAMAGE.
 
 #ifdef WITH_WEBSOCKETS
 
+#include "config.h"
+
 #include <libwebsockets.h>
 #include "mosquitto_internal.h"
 #include "mosquitto_broker_internal.h"