utils: show error message when priority is missing (#452)

* p4runtime_lib/helper: use more appropriate variable names

Suggested-by: Antonin Bas <abas@vmware.com>
Signed-off-by: Radostin Stoyanov <rstoyanov@fedoraproject.org>

* utils: show error message when priority is missing

A 'priority' field is required to order entries when the
table's match key includes an optional, ternary or range match.

Suggested-by: Andy Fingerhut <andy_fingerhut@alum.wustl.edu>
Signed-off-by: Radostin Stoyanov <rstoyanov@fedoraproject.org>

utils/run_exercise.py

@@ -273,7 +273,9 @@ class ExerciseRunner:
                 device_id=device_id,
                 sw_conf_file=sw_conf_file,
                 workdir=os.getcwd(),
-                proto_dump_fpath=outfile)
+                proto_dump_fpath=outfile,
+                runtime_json=runtime_json
+            )
 
     def program_switch_cli(self, sw_name, sw_dict):
         """ This method will start up the CLI and use the contents of the