fix return types for aio_read and aio_write again

previous fix was backwards and propagated the wrong type rather than
the right one...

include/aio.h

@@ -41,8 +41,8 @@ struct aiocb {
 #define LIO_WAIT 0
 #define LIO_NOWAIT 1
 
-ssize_t aio_read(struct aiocb *);
-ssize_t aio_write(struct aiocb *);
+int aio_read(struct aiocb *);
+int aio_write(struct aiocb *);
 int aio_error(const struct aiocb *);
 ssize_t aio_return(struct aiocb *);
 int aio_cancel(int, struct aiocb *);

src/aio/aio_readwrite.c

@@ -91,13 +91,13 @@ static int new_req(struct aiocb *cb)
 	return ret;
 }
 
-ssize_t aio_read(struct aiocb *cb)
+int aio_read(struct aiocb *cb)
 {
 	cb->aio_lio_opcode = LIO_READ;
 	return new_req(cb);
 }
 
-ssize_t aio_write(struct aiocb *cb)
+int aio_write(struct aiocb *cb)
 {
 	cb->aio_lio_opcode = LIO_WRITE;
 	return new_req(cb);