zio-trigger.h: bugfix: missing prototype zio_trigger_abort()

Signed-off-by: Federico Vaga <federico.vaga@gmail.com>
Acked-by: Alessandro Rubini <rubini@gnudd.com>

include/linux/zio-trigger.h

@@ -106,5 +106,6 @@ struct zio_trigger_operations {
 };
 
 void zio_generic_data_done(struct zio_cset *cest);
+void zio_trigger_abort(struct zio_cset *cset);
 
 #endif /* __ZIO_TRIGGER_H__ */