options/glibc: define SIOC[GS]IFMTU in sys/ioctl.h
@@ -24,6 +24,8 @@ int ioctl(int fd, unsigned long request, ...);
#define SIOCGIFCONF 0x8912
#define SIOCGIFFLAGS 0x8913
#define SIOCSIFFLAGS 0x8914
+#define SIOCGIFMTU 0x8921
+#define SIOCSIFMTU 0x8922
#define SIOCGIFINDEX 0x8933
#define SIOCPROTOPRIVATE 0x89E0
