[CVE-2009-0029] Convert all system calls to return a long

Convert all system calls to return a long. This should be a NOP since all
converted types should have the same size anyway.
With the exception of sys_exit_group which returned void. But that doesn't
matter since the system call doesn't return.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

ipc/mqueue.c

@@ -907,7 +907,7 @@ out:
 	return ret;
 }
 
-asmlinkage ssize_t sys_mq_timedreceive(mqd_t mqdes, char __user *u_msg_ptr,
+asmlinkage long sys_mq_timedreceive(mqd_t mqdes, char __user *u_msg_ptr,
 	size_t msg_len, unsigned int __user *u_msg_prio,
 	const struct timespec __user *u_abs_timeout)
 {