build: Include sys/socket.h for AF_UNSPEC
diff --git a/openbsc/src/libmsc/meas_feed.c b/openbsc/src/libmsc/meas_feed.c
index 86d679a..5fc7c49 100644
--- a/openbsc/src/libmsc/meas_feed.c
+++ b/openbsc/src/libmsc/meas_feed.c
@@ -2,6 +2,8 @@
 
 #include <unistd.h>
 
+#include <sys/socket.h>
+
 #include <osmocom/core/msgb.h>
 #include <osmocom/core/socket.h>
 #include <osmocom/core/write_queue.h>