[gn build] Port 3081d52d8242 (#193862)

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

diff --git a/llvm/utils/gn/secondary/llvm/unittests/MC/BUILD.gn b/llvm/utils/gn/secondary/llvm/unittests/MC/BUILD.gn
index 36027f4..b9fcb0d 100644
--- a/llvm/utils/gn/secondary/llvm/unittests/MC/BUILD.gn
+++ b/llvm/utils/gn/secondary/llvm/unittests/MC/BUILD.gn
@@ -10,6 +10,7 @@
   ]
   sources = [
     "Disassembler.cpp",
+    "DwarfDebugFrameCIE.cpp",
     "DwarfLineTableHeaders.cpp",
     "DwarfLineTables.cpp",
     "MCDisassemblerTest.cpp",