On unknown CPUs, don't run the MSR consistency test in the full testsuite

On unknown CPUs without a CPU-specific MSR blacklist, this test produces
too many false positives.  Leave it available to run specifically, but
don't run it as part of the full "run all tests" testsuite.

Author: joshtriplett

python/cpu_gen.py

@@ -39,7 +39,7 @@ def init():
     pass
 
 def register_tests():
-    testsuite.add_test("MSR consistency test", msr_test)
+    testsuite.add_test("MSR consistency test", msr_test, runall=False)
 
 def msr_test():
     testmsr.rdmsr_consistent(msr_blacklist, msr_masklist)