Doc: fix capitalization of BAR Descriptor

In the Issues output pane filter.

Change-Id: I3283628f74dd48c2e95eeedad93ce28f1686c25f
Reviewed-by: Leena Miettinen <riitta-leena.miettinen@theqtcompany.com>

doc/src/howto/creator-ui.qdoc

@@ -329,7 +329,7 @@
         \li \uicontrol Analyzer - Errors encountered while running the
             \l{Analyzing Code}{Valgrind code analysis tools}.
 
-        \li \uicontrol {Bar Descriptor} - Errors and warnings encountered when using
+        \li \uicontrol {BAR Descriptor} - Errors and warnings encountered when using
             the BlackBerry 10 BAR descriptor editor to customize the appearance
             and behavior of an application.