[gn] attempt to port 6885810 (vcsrevision dep in Support)

Author: nico

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

@@ -3,6 +3,7 @@ static_library("Support") {
   deps = [
     "BLAKE3",
     "//llvm/include/llvm/Config:config",
+    "//llvm/include/llvm/Support:write_vcsrevision",
     "//llvm/lib/Demangle",
     "//llvm/utils/gn/build/libs/pthread",
     "//llvm/utils/gn/build/libs/terminfo",