Split out -verify into two distinct option flags

Instead of dual-purposing a single flag, rename the driver option to
--verify-debug-info.

The frontend -verify option that enables diagnostic verification remains
unchanged except that it's now a pure CC1Option.

Both have been given proper help text.

llvm-svn: 199451
diff --git a/clang/lib/Driver/Driver.cpp b/clang/lib/Driver/Driver.cpp
index 65df188..ad938b8 100644
--- a/clang/lib/Driver/Driver.cpp
+++ b/clang/lib/Driver/Driver.cpp
@@ -935,8 +935,8 @@
         Actions.push_back(new DsymutilJobAction(Inputs, types::TY_dSYM));
       }
 
-      // Verify the output (debug information only) if we passed '-verify'.
-      if (Args.hasArg(options::OPT_verify)) {
+      // Verify the output (debug information only for now).
+      if (Args.hasArg(options::OPT_verify_debug_info)) {
         ActionList VerifyInputs;
         VerifyInputs.push_back(Actions.back());
         Actions.pop_back();