BugPoint: Fix some memory leaks.

Patch by Kostya Serebryany.

unique_ptr would be nice, but it's a bit too much work for an area I'm
not familiar with, nor invested in, unfortunately.

llvm-svn: 207265

llvm/tools/bugpoint/BugDriver.cpp

@@ -76,6 +76,10 @@ BugDriver::BugDriver(const char *toolname, bool find_bugs,
 
 BugDriver::~BugDriver() {
   delete Program;
+  if (Interpreter != SafeInterpreter)
+    delete Interpreter;
+  delete SafeInterpreter;
+  delete gcc;
 }