[bazel] Port llvm#155026: OptTable support for subcommands (llvm#162150)

Author: rupprecht

utils/bazel/llvm-project-overlay/llvm/BUILD.bazel

@@ -770,6 +770,7 @@ cc_binary(
     stamp = 0,
     deps = [
         ":CodeGenTypes",
+        ":Option",
         ":Support",
         ":TableGen",
         ":TableGenGlobalISel",

utils/bazel/llvm-project-overlay/llvm/unittests/BUILD.bazel

@@ -650,6 +650,15 @@ gentbl_cc_library(
     deps = ["//llvm:OptParserTdFiles"],
 )
 
+gentbl_cc_library(
+    name = "sub_command_opts_tests_gen",
+    strip_include_prefix = "Option",
+    tbl_outs = {"Option/SubCommandOpts.inc": ["-gen-opt-parser-defs"]},
+    tblgen = "//llvm:llvm-tblgen",
+    td_file = "Option/SubCommandOpts.td",
+    deps = ["//llvm:OptParserTdFiles"],
+)
+
 gentbl_cc_library(
     name = "automata_gen",
     strip_include_prefix = "TableGen",
@@ -671,6 +680,7 @@ cc_test(
     ),
     deps = [
         ":option_tests_gen",
+        ":sub_command_opts_tests_gen",
         "//llvm:Option",
         "//llvm:Support",
         "//third-party/unittest:gtest",