[gn build] Port a449b85

Author: llvmgnsyncbot

llvm/utils/gn/secondary/llvm/lib/Target/AMDGPU/BUILD.gn

@@ -209,7 +209,6 @@ static_library("LLVMAMDGPUCodeGen") {
     "GCNVOPDUtils.cpp",
     "R600AsmPrinter.cpp",
     "R600ClauseMergePass.cpp",
-    "R600CodeGenPassBuilder.cpp",
     "R600ControlFlowFinalizer.cpp",
     "R600EmitClauseMarkers.cpp",
     "R600ExpandSpecialInstrs.cpp",