Propagate soffice process failure from OfficeConnection's tearDown

...which had gone missing with 98cbfb087e "uitest:
kill the LibreOffice instance if it ignores terminate request".

(None != 0 is true, so there is no need to map from ret_attr to ret, and that
code can be cleaned up a bit.)

Change-Id: Ic5e429d61a10a2bbd5c28aeee9d8465cb05c1e4a
Reviewed-on: https://gerrit.libreoffice.org/80147
Tested-by: Jenkins
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>

uitest/libreoffice/connection.py

@@ -134,14 +134,12 @@ class OfficeConnection:
             time_ = 0
             while time_ < 30:
                 time_ += DEFAULT_SLEEP
-                ret_attr = self.soffice.poll()
-                if ret_attr is not None:
+                ret = self.soffice.poll()
+                if ret is not None:
                     break
                 time.sleep(DEFAULT_SLEEP)
 
-            ret = 0
-            if ret_attr is None:
-                ret = 1
+            if ret is None:
                 self.soffice.terminate()
 
             # ret = self.soffice.wait()