NFC: Fix some darwin linker warnings introduced in r338385

[erik.pilkington]

Summary

The darwin linker was complaining about Toolchains/RISCV.cpp and Toolchains/Arch/RISCV.cpp had the same name. Fix is to just rename Toolchains/RISCV.cpp to Toolchains/RISCVToolchain.cpp. This was introduced by D50246.

/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/libtool: warning same member name (RISCV.cpp.o) in output file used for input files: tools/clang/lib/Driver/CMakeFiles/clangDriver.dir/ToolChains/Arch/RISCV.cpp.o and: tools/clang/lib/Driver/CMakeFiles/clangDriver.dir/ToolChains/RISCV.cpp.o (due to use of basename, truncation, blank padding or duplicate input files)

rdar://44535427

[xbolva00]

ok, thanks

clang/lib/Driver/CMakeLists.txt

add_clang_library(clangDriver
   ToolChains/MinGW.cpp
   ToolChains/Minix.cpp
   ToolChains/MSVC.cpp
   ToolChains/Myriad.cpp
   ToolChains/NaCl.cpp
   ToolChains/NetBSD.cpp
   ToolChains/OpenBSD.cpp
   ToolChains/PS4CPU.cpp
-  ToolChains/RISCV.cpp
+  ToolChains/RISCVToolchain.cpp
   ToolChains/Solaris.cpp
   ToolChains/TCE.cpp
   ToolChains/WebAssembly.cpp
   ToolChains/XCore.cpp
   Types.cpp
   XRayArgs.cpp
 
   DEPENDS
   ClangDriverOptions
 
   LINK_LIBS
   clangBasic
   ${system_libs}
   )

clang/lib/Driver/Driver.cpp

 #include "ToolChains/MinGW.h"
 #include "ToolChains/Minix.h"
 #include "ToolChains/MipsLinux.h"
 #include "ToolChains/Myriad.h"
 #include "ToolChains/NaCl.h"
 #include "ToolChains/NetBSD.h"
 #include "ToolChains/OpenBSD.h"
 #include "ToolChains/PS4CPU.h"
-#include "ToolChains/RISCV.h"
+#include "ToolChains/RISCVToolchain.h"
 #include "ToolChains/Solaris.h"
 #include "ToolChains/TCE.h"
 #include "ToolChains/WebAssembly.h"
 #include "ToolChains/XCore.h"
 #include "clang/Basic/Version.h"
 #include "clang/Basic/VirtualFileSystem.h"
 #include "clang/Config/config.h"
 #include "clang/Driver/Action.h"

clang/lib/Driver/ToolChains/RISCVToolchain.h

-//===--- RISCV.h - RISCV ToolChain Implementations --------------*- C++ -*-===//
+//===--- RISCVToolchain.h - RISCV ToolChain Implementations -----*- C++ -*-===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_CLANG_LIB_DRIVER_TOOLCHAINS_RISCV_H
-#define LLVM_CLANG_LIB_DRIVER_TOOLCHAINS_RISCV_H
+#ifndef LLVM_CLANG_LIB_DRIVER_TOOLCHAINS_RISCVTOOLCHAIN_H
+#define LLVM_CLANG_LIB_DRIVER_TOOLCHAINS_RISCVTOOLCHAIN_H
 
 #include "Gnu.h"
 #include "clang/Driver/ToolChain.h"
 
 namespace clang {
 namespace driver {
 namespace toolchains {
 

clang/lib/Driver/ToolChains/RISCVToolchain.cpp

-//===--- RISCV.cpp - RISCV ToolChain Implementations ------------*- C++ -*-===//
+//===--- RISCVToolchain.cpp - RISCV ToolChain Implementations ---*- C++ -*-===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 
-#include "RISCV.h"
+#include "RISCVToolchain.h"
 #include "CommonArgs.h"
 #include "InputInfo.h"
 #include "clang/Driver/Compilation.h"
 #include "clang/Driver/Options.h"
 #include "llvm/Option/ArgList.h"
 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/Path.h"
 #include "llvm/Support/raw_ostream.h"