Fix compilation problem with USHRT_MAX and UCHAR_MAX
diff --git a/src/sdp.c b/src/sdp.c
index 40d694d..3b1a5d9 100644
--- a/src/sdp.c
+++ b/src/sdp.c
@@ -30,9 +30,10 @@
 
 #include <stdio.h>
 #include <errno.h>
-#include <unistd.h>
 #include <fcntl.h>
+#include <unistd.h>
 #include <stdlib.h>
+#include <limits.h>
 #include <malloc.h>
 #include <syslog.h>
 #include <sys/un.h>