[gn build] Port 3bf91ad

Author: llvmgnsyncbot

llvm/utils/gn/secondary/llvm/lib/CodeGen/BUILD.gn

@@ -50,6 +50,7 @@ static_library("CodeGen") {
     "DFAPacketizer.cpp",
     "DeadMachineInstructionElim.cpp",
     "DetectDeadLanes.cpp",
+    "DroppedVariableStatsMIR.cpp",
     "DwarfEHPrepare.cpp",
     "EHContGuardCatchret.cpp",
     "EarlyIfConversion.cpp",

llvm/utils/gn/secondary/llvm/unittests/CodeGen/BUILD.gn

@@ -26,6 +26,7 @@ unittest("CodeGenTests") {
     "CCStateTest.cpp",
     "DIEHashTest.cpp",
     "DIETest.cpp",
+    "DroppedVariableStatsMIRTest.cpp",
     "DwarfStringPoolEntryRefTest.cpp",
     "InstrRefLDVTest.cpp",
     "LexicalScopesTest.cpp",