coroipcs.h: avoid 3 warnings

* exec/coroipcs.h: Forward-declare "struct iovec".

git-svn-id: http://svn.fedorahosted.org/svn/corosync/trunk@1948 fd59a12c-fef9-0310-b244-a6a79926bd2f

exec/coroipcs.h

@@ -39,6 +39,8 @@
 
 #define SOCKET_SERVICE_INIT 0xFFFFFFFF
 
+struct iovec;
+
 typedef int (*coroipcs_init_fn_lvalue) (void *conn);
 typedef int (*coroipcs_exit_fn_lvalue) (void *conn);
 typedef void (*coroipcs_handler_fn_lvalue) (void *conn, void *msg);