[gn] port eeee5a4 (clang-sycl-linker)

Also port follow-up 0d499f9.

Author: nico

llvm/utils/gn/secondary/clang/test/BUILD.gn

@@ -173,6 +173,7 @@ group("test") {
     "//clang/tools/clang-refactor",
     "//clang/tools/clang-repl",
     "//clang/tools/clang-scan-deps",
+    "//clang/tools/clang-sycl-linker",
     "//clang/tools/diagtool",
     "//clang/tools/driver:symlinks",
     "//clang/unittests",

llvm/utils/gn/secondary/clang/tools/clang-sycl-linker/BUILD.gn

@@ -0,0 +1,19 @@
+import("//llvm/utils/TableGen/tablegen.gni")
+
+tablegen("SYCLLinkOpts") {
+  args = [ "-gen-opt-parser-defs" ]
+}
+
+executable("clang-sycl-linker") {
+  configs += [ "//llvm/utils/gn/build:clang_code" ]
+  deps = [
+    ":SYCLLinkOpts",
+    "//clang/lib/Basic",
+    "//llvm/lib/BinaryFormat",
+    "//llvm/lib/Option",
+    "//llvm/lib/Object",
+    "//llvm/lib/Support",
+    "//llvm/lib/TargetParser",
+  ]
+  sources = [ "ClangSYCLLinker.cpp" ]
+}