merge run-gem5-se into run

This way it can re-use run functionality, notably setting gem5.opt
generic args, and putting m5out where it belongs.

bench-boot

@@ -71,7 +71,7 @@ fi
 if [ "$test_size" -ge 3 ]; then
   #bench "$arch --eval 'm5 exit' --gem5 -- --cpu-type=HPI ${caches}"
   #gem5_insts "$arch"
-  bench "$arch --eval 'm5 exit' --gem5 --gem5-biglittle"
+  bench "$arch --eval 'm5 exit' --gem5 --gem5-script biglittle"
   gem5_insts "$arch"
 fi