configs: Alter x86-npb-benchmarks.py to exit after WORKEND

While the config script will still function without exiting the SimLoop
after the "WORKEND" exit event, there's no need for the simulation to
continue beyond this point.

Change-Id: I60691215e9516fa1eeb8b8502f2bc5a09de2969b
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/66513
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Bobby Bruce <bbruce@ucdavis.edu>

configs/example/gem5_library/x86-npb-benchmarks.py

@@ -237,12 +237,11 @@ def handle_workbegin():
 # marked by `workend`.
 
 # We exepect that ROI ends with `workend` or `simulate() limit reached`.
-# Otherwise the simulation ended unexpectedly.
 def handle_workend():
     print("Dump stats at the end of the ROI!")
 
     m5.stats.dump()
-    yield False
+    yield True
 
 
 simulator = Simulator(