Add missing "llvm/Support/Host.h" header to LLVM example after recent header trimming (NFC)

Author: Mehdi Amini

llvm/examples/Kaleidoscope/Chapter9/toy.cpp

@@ -7,6 +7,7 @@
 #include "llvm/IR/LegacyPassManager.h"
 #include "llvm/IR/Module.h"
 #include "llvm/IR/Verifier.h"
+#include "llvm/Support/Host.h"
 #include "llvm/Support/TargetSelect.h"
 #include "llvm/Transforms/Scalar.h"
 #include <cctype>

llvm/examples/ThinLtoJIT/ThinLtoJIT.cpp

@@ -9,6 +9,7 @@
 #include "llvm/ExecutionEngine/Orc/RTDyldObjectLinkingLayer.h"
 #include "llvm/ExecutionEngine/SectionMemoryManager.h"
 #include "llvm/Support/Debug.h"
+#include "llvm/Support/Host.h"
 
 #include "ThinLtoDiscoveryThread.h"
 #include "ThinLtoInstrumentationLayer.h"