Move multicast address identification fallback macros to network.h from udp.c

Originally committed as revision 25386 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavformat/network.h

@@ -155,4 +155,11 @@ const char *ff_gai_strerror(int ecode);
 #define INET6_ADDRSTRLEN INET_ADDRSTRLEN
 #endif
 
+#ifndef IN_MULTICAST
+#define IN_MULTICAST(a) ((((uint32_t)(a)) & 0xf0000000) == 0xe0000000)
+#endif
+#ifndef IN6_IS_ADDR_MULTICAST
+#define IN6_IS_ADDR_MULTICAST(a) (((uint8_t *) (a))[0] == 0xff)
+#endif
+
 #endif /* AVFORMAT_NETWORK_H */

libavformat/udp.c

@@ -40,12 +40,6 @@
 #define IPV6_ADD_MEMBERSHIP IPV6_JOIN_GROUP
 #define IPV6_DROP_MEMBERSHIP IPV6_LEAVE_GROUP
 #endif
-#ifndef IN_MULTICAST
-#define IN_MULTICAST(a) ((((uint32_t)(a)) & 0xf0000000) == 0xe0000000)
-#endif
-#ifndef IN6_IS_ADDR_MULTICAST
-#define IN6_IS_ADDR_MULTICAST(a) (((uint8_t *) (a))[0] == 0xff)
-#endif
 
 typedef struct {
     int udp_fd;