[IR] Split out target specific intrinsic enums into separate headers

This has two main effects:
- Optimizes debug info size by saving 221.86 MB of obj file size in a
  Windows optimized+debug build of 'all'. This is 3.03% of 7,332.7MB of
  object file size.
- Incremental step towards decoupling target intrinsics.

The enums are still compact, so adding and removing a single
target-specific intrinsic will trigger a rebuild of all of LLVM.
Assigning distinct target id spaces is potential future work.

Part of PR34259

Reviewers: efriedma, echristo, MaskRay

Reviewed By: echristo, MaskRay

Differential Revision: https://reviews.llvm.org/D71320
diff --git a/clang/lib/CodeGen/CGBuiltin.cpp b/clang/lib/CodeGen/CGBuiltin.cpp
index 8a53739..29226d6 100644
--- a/clang/lib/CodeGen/CGBuiltin.cpp
+++ b/clang/lib/CodeGen/CGBuiltin.cpp
@@ -31,6 +31,17 @@
 #include "llvm/IR/DataLayout.h"
 #include "llvm/IR/InlineAsm.h"
 #include "llvm/IR/Intrinsics.h"
+#include "llvm/IR/IntrinsicsAArch64.h"
+#include "llvm/IR/IntrinsicsAMDGPU.h"
+#include "llvm/IR/IntrinsicsARM.h"
+#include "llvm/IR/IntrinsicsBPF.h"
+#include "llvm/IR/IntrinsicsHexagon.h"
+#include "llvm/IR/IntrinsicsNVPTX.h"
+#include "llvm/IR/IntrinsicsPowerPC.h"
+#include "llvm/IR/IntrinsicsR600.h"
+#include "llvm/IR/IntrinsicsS390.h"
+#include "llvm/IR/IntrinsicsWebAssembly.h"
+#include "llvm/IR/IntrinsicsX86.h"
 #include "llvm/IR/MDBuilder.h"
 #include "llvm/Support/ConvertUTF.h"
 #include "llvm/Support/ScopedPrinter.h"