Fixes for the problem where two TargetDirAnnotation

cause Driver.execute to fail.
This eliminates an, I believe, unnecessary call to getAnnotations which is causing the duplication.
getAnnotations is used internally by Driver.execute and it is where the TargetDirAnnotation is added.

src/main/scala/simulate.scala

@@ -75,8 +75,6 @@ object simulate {
 
   def build(optionsManager: SimulatorOptionsManager, conf: CPUConfig): String = {
     optionsManager.firrtlOptions = optionsManager.firrtlOptions.copy(compilerName = "low")
-    val annos = firrtl.Driver.getAnnotations(optionsManager)
-    optionsManager.firrtlOptions = optionsManager.firrtlOptions.copy(annotations = annos.toList)
 
     chisel3.Driver.execute(optionsManager, () => new Top(conf)) match {
     case ChiselExecutionSuccess(Some(_), _, Some(firrtlExecutionResult)) =>

src/main/scala/testing/CPUTesterDriver.scala

@@ -21,9 +21,7 @@ class CPUTesterDriver(cpuType: String,
   val optionsManager = new SimulatorOptionsManager()
 
   if (optionsManager.targetDirName == ".") {
-    // TODO: Revert this either by waiting for the chisel guys to fix the CWD bug, or moving the testing system over to
-    // FIRRTLMain instead of Driver
-    //optionsManager.setTargetDirName(s"test_run_dir/$cpuType/$binary$extraName")
+    optionsManager.setTargetDirName(s"test_run_dir/$cpuType/$binary$extraName")
   }
 
   val hexName = s"${optionsManager.targetDirName}/${binary}.hex"