Don't #include ClangPersistentVariables.h from Process.h

Nothing from this header file was even being referenced in
Process.h anyway, so it was a completely unnecessary include.

llvm-svn: 231131
diff --git a/lldb/source/Plugins/UnwindAssembly/x86/UnwindAssembly-x86.cpp b/lldb/source/Plugins/UnwindAssembly/x86/UnwindAssembly-x86.cpp
index 010e3f0..91f6006 100644
--- a/lldb/source/Plugins/UnwindAssembly/x86/UnwindAssembly-x86.cpp
+++ b/lldb/source/Plugins/UnwindAssembly/x86/UnwindAssembly-x86.cpp
@@ -10,6 +10,7 @@
 #include "UnwindAssembly-x86.h"
 
 #include "llvm-c/Disassembler.h"
+#include "llvm/ADT/STLExtras.h"
 #include "llvm/Support/TargetSelect.h"
 
 #include "lldb/Core/Address.h"