[iwyu] Fix some header include regression

Running iwyu-diff from https://github.com/serge-sans-paille/preprocessor-utils
makes it possible to quickly spot regression in unused includes. This patch
contains the few regressions since the last header cleanup.

Differential Revision: https://reviews.llvm.org/D123036

llvm/lib/IR/FPEnv.cpp

@@ -14,7 +14,7 @@
 
 #include "llvm/IR/FPEnv.h"
 #include "llvm/ADT/StringSwitch.h"
-#include "llvm/IR/InstrTypes.h"
+#include "llvm/IR/Instruction.h"
 #include "llvm/IR/IntrinsicInst.h"
 #include "llvm/IR/Intrinsics.h"
 

llvm/lib/Target/MSP430/MSP430ISelDAGToDAG.cpp

@@ -18,7 +18,6 @@
 #include "llvm/CodeGen/MachineRegisterInfo.h"
 #include "llvm/CodeGen/SelectionDAG.h"
 #include "llvm/CodeGen/SelectionDAGISel.h"
-#include "llvm/CodeGen/TargetLowering.h"
 #include "llvm/Config/llvm-config.h"
 #include "llvm/IR/CallingConv.h"
 #include "llvm/IR/Constants.h"

llvm/lib/Target/NVPTX/NVPTXAsmPrinter.cpp

@@ -45,7 +45,6 @@
 #include "llvm/CodeGen/MachineModuleInfo.h"
 #include "llvm/CodeGen/MachineOperand.h"
 #include "llvm/CodeGen/MachineRegisterInfo.h"
-#include "llvm/CodeGen/TargetLowering.h"
 #include "llvm/CodeGen/TargetRegisterInfo.h"
 #include "llvm/CodeGen/ValueTypes.h"
 #include "llvm/IR/Attributes.h"

llvm/lib/Target/NVPTX/NVPTXISelLowering.cpp

@@ -35,6 +35,7 @@
 #include "llvm/IR/Constants.h"
 #include "llvm/IR/DataLayout.h"
 #include "llvm/IR/DerivedTypes.h"
+#include "llvm/IR/FPEnv.h"
 #include "llvm/IR/Function.h"
 #include "llvm/IR/GlobalValue.h"
 #include "llvm/IR/Instruction.h"
@@ -48,7 +49,6 @@
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/MachineValueType.h"
-#include "llvm/Support/MathExtras.h"
 #include "llvm/Support/raw_ostream.h"
 #include "llvm/Target/TargetMachine.h"
 #include "llvm/Target/TargetOptions.h"

llvm/lib/Transforms/Scalar/Float2Int.cpp

@@ -27,7 +27,6 @@
 #include "llvm/Support/raw_ostream.h"
 #include "llvm/Transforms/Scalar.h"
 #include <deque>
-#include <functional> // For std::function
 
 #define DEBUG_TYPE "float2int"