[llvm] Stop including llvm/ADT/StringMap.h (NFC)

These source files do not use StringMap.

llvm/lib/CodeGen/AsmPrinter/AccelTable.cpp

@@ -13,7 +13,6 @@
 #include "llvm/CodeGen/AccelTable.h"
 #include "DwarfCompileUnit.h"
 #include "llvm/ADT/STLExtras.h"
-#include "llvm/ADT/StringMap.h"
 #include "llvm/ADT/Twine.h"
 #include "llvm/BinaryFormat/Dwarf.h"
 #include "llvm/CodeGen/AsmPrinter.h"

llvm/lib/CodeGen/MIRParser/MIRParser.cpp

@@ -13,7 +13,6 @@
 
 #include "llvm/CodeGen/MIRParser/MIRParser.h"
 #include "llvm/ADT/DenseMap.h"
-#include "llvm/ADT/StringMap.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/AsmParser/Parser.h"
 #include "llvm/AsmParser/SlotMapping.h"

llvm/lib/ExecutionEngine/JITLink/COFFLinkGraphBuilder.h

@@ -14,7 +14,6 @@
 #define LIB_EXECUTIONENGINE_JITLINK_COFFLINKGRAPHBUILDER_H
 
 #include "llvm/ADT/DenseMap.h"
-#include "llvm/ADT/StringMap.h"
 #include "llvm/ExecutionEngine/JITLink/JITLink.h"
 #include "llvm/Object/COFF.h"
 

llvm/lib/Object/ModuleSymbolTable.cpp

@@ -15,7 +15,6 @@
 #include "llvm/Object/ModuleSymbolTable.h"
 #include "RecordStreamer.h"
 #include "llvm/ADT/STLExtras.h"
-#include "llvm/ADT/StringMap.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/IR/Function.h"
 #include "llvm/IR/GlobalAlias.h"

llvm/lib/Transforms/IPO/FunctionImport.cpp

@@ -16,7 +16,6 @@
 #include "llvm/ADT/SetVector.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/Statistic.h"
-#include "llvm/ADT/StringMap.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/Bitcode/BitcodeReader.h"
 #include "llvm/IR/AutoUpgrade.h"