systemc: Make verify.py ignore another warning.

Also make warning filters more general and easier to add by writing a
function to generate them.

Change-Id: I8d813ded9ad8a9ccac4e48e5ea80a3c9c23959da
Reviewed-on: https://gem5-review.googlesource.com/12061
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

src/systemc/tests/verify.py

@@ -190,10 +190,15 @@ class LogChecker(Checker):
         filts = '|'.join(filts)
         return re.compile(filts, flags=re.MULTILINE)
 
+    def warning_filt(num):
+        return (r'^\nWarning: \(W{}\) .*\n(In file: .*\n)?'
+                r'(In process: [\w.]* @ .*\n)?').format(num)
+
     ref_filt = merge_filts(
         r'^\nInfo: /OSCI/SystemC: Simulation stopped by user.\n',
         r'^SystemC Simulation\n',
-        r'^\nWarning: .*\nIn file: .*\n'
+        warning_filt(571),
+        warning_filt(540)
     )
     test_filt = merge_filts(
         r'^Global frequency set at \d* ticks per second\n'