Docu: genericirq.rst: fix irq-example

A code example was missing the pointer to dereference a variable.
Signed-off-by: Philipp Stanner <pstanner@redhat.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20230824110109.18844-1-pstanner@redhat.com

Documentation/core-api/genericirq.rst

@@ -264,7 +264,7 @@ The following control flow is implemented (simplified excerpt)::
             desc->irq_data.chip->irq_unmask();
         desc->status &= ~pending;
         handle_irq_event(desc->action);
-    } while (status & pending);
+    } while (desc->status & pending);
     desc->status &= ~running;