rbd: clean up, fix style

No assignment in condition.  Remove duplicate ret > 0 check.

Signed-off-by: Sage Weil <sage@newdream.net>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

block/rbd.c

@@ -391,15 +391,14 @@ static void qemu_rbd_aio_event_reader(void *opaque)
         char *p = (char *)&s->event_rcb;
 
         /* now read the rcb pointer that was sent from a non qemu thread */
-        if ((ret = read(s->fds[RBD_FD_READ], p + s->event_reader_pos,
-                        sizeof(s->event_rcb) - s->event_reader_pos)) > 0) {
-            if (ret > 0) {
-                s->event_reader_pos += ret;
-                if (s->event_reader_pos == sizeof(s->event_rcb)) {
-                    s->event_reader_pos = 0;
-                    qemu_rbd_complete_aio(s->event_rcb);
-                    s->qemu_aio_count--;
-                }
+        ret = read(s->fds[RBD_FD_READ], p + s->event_reader_pos,
+                   sizeof(s->event_rcb) - s->event_reader_pos);
+        if (ret > 0) {
+            s->event_reader_pos += ret;
+            if (s->event_reader_pos == sizeof(s->event_rcb)) {
+                s->event_reader_pos = 0;
+                qemu_rbd_complete_aio(s->event_rcb);
+                s->qemu_aio_count--;
             }
         }
     } while (ret < 0 && errno == EINTR);