hmp: block-stream: fix typo

Found this by enabling C++ errors.  The bool and enum arguments
are mistakenly flipped.

Signed-off-by: Anthony Liguori <anthony@codemonkey.ws>
diff --git a/hmp.c b/hmp.c
index 2a90295..5891507 100644
--- a/hmp.c
+++ b/hmp.c
@@ -1163,7 +1163,7 @@
 
     qmp_block_stream(device, base != NULL, base,
                      qdict_haskey(qdict, "speed"), speed,
-                     BLOCKDEV_ON_ERROR_REPORT, true, &error);
+                     true, BLOCKDEV_ON_ERROR_REPORT, &error);
 
     hmp_handle_error(mon, &error);
 }