[Support] Remove unnecessary includes (NFC)

Author: kazutakahirata

llvm/include/llvm/Support/LLVMDriver.h

@@ -9,8 +9,6 @@
 #ifndef LLVM_SUPPORT_LLVMDRIVER_H
 #define LLVM_SUPPORT_LLVMDRIVER_H
 
-#include "llvm/ADT/SmallVector.h"
-
 namespace llvm {
 
 struct ToolContext {

llvm/unittests/Support/Chrono.cpp

@@ -7,7 +7,6 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/Support/Chrono.h"
-#include "llvm/ADT/SmallVector.h"
 #include "llvm/Support/FormatVariadic.h"
 #include "gtest/gtest.h"
 

llvm/unittests/Support/CommandLineTest.cpp

@@ -28,7 +28,6 @@
 #include <fstream>
 #include <stdlib.h>
 #include <string>
-#include <tuple>
 
 using namespace llvm;
 using llvm::unittest::TempDir;

llvm/unittests/Support/InstructionCostTest.cpp

@@ -8,7 +8,6 @@
 
 #include "llvm/Support/InstructionCost.h"
 #include "gtest/gtest.h"
-#include <limits>
 
 using namespace llvm;
 

llvm/unittests/Support/MemoryTest.cpp

@@ -9,7 +9,6 @@
 #include "llvm/Support/Memory.h"
 #include "llvm/Support/Process.h"
 #include "gtest/gtest.h"
-#include <cassert>
 #include <cstdlib>
 
 #if defined(__NetBSD__)