[LLVM][Hexagon] Revert LLVM header change for version 14 (apache#10006)

* Revert LLVM header change

* Trigger

Author: mehrdadh

cmake/modules/Hexagon.cmake

@@ -301,9 +301,6 @@ if(USE_HEXAGON_RPC)
     ${HEXAGON_RPC_OUTPUT} COPYONLY)
 
   set_directory_properties(PROPERTIES ADDITIONAL_MAKE_CLEAN_FILES "${HEXAGON_RPC_OUTPUT}")
-
-  # Used in `src/target/llvm/llvm_common.h`
-  add_definitions(-DTVM_USE_HEXAGON_LLVM)
 endif()
 
 if(USE_HEXAGON_DEVICE STREQUAL "${PICK_SIM}")

src/target/llvm/llvm_common.h

@@ -71,7 +71,7 @@
 #include <llvm/Support/FileSystem.h>
 #include <llvm/Support/Host.h>
 #include <llvm/Support/MemoryBuffer.h>
-#if TVM_LLVM_VERSION >= 140 && !defined(TVM_USE_HEXAGON_LLVM)
+#if TVM_LLVM_VERSION >= 140
 #include <llvm/MC/TargetRegistry.h>
 #else
 #include <llvm/Support/TargetRegistry.h>