Replace UTF-8 no-break space to ASCII space

UTF-8 no-break space causes C4819 warning in MSVC with CP932.

Change-Id: I83a6ea6d060d132d21d8ea3141051f850d0e6bd2
Reviewed-on: https://gerrit.libreoffice.org/8628Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>

include/cppuhelper/weak.hxx

@@ -163,8 +163,8 @@ public:
     To be used like:
 
     css::uno::XInterface * FOO_constructor_function(...) {
-        return cppu::acquire(new FOO(...));
-    }
+        return cppu::acquire(new FOO(...));
+    }
 
     @param instance
     Newly created instance that should be acquired.