Drop superfluous includes of qapi/qmp/qerror.h

Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-6-armbru@redhat.com>

blockdev-nbd.c

@@ -14,7 +14,6 @@
 #include "sysemu/block-backend.h"
 #include "hw/block/block.h"
 #include "qapi/error.h"
-#include "qapi/qmp/qerror.h"
 #include "sysemu/sysemu.h"
 #include "qmp-commands.h"
 #include "block/nbd.h"