Add support for option -time-transforms which causes the pass manager to emit time information for each transform run.

Swift SVN r14042

lib/Frontend/CompilerInvocation.cpp

@@ -632,6 +632,7 @@ static bool ParseSILArgs(SILOptions &Opts, ArgList &Args,
   Opts.EnableARCOptimizations = !Args.hasArg(OPT_disable_arc_opts);
   Opts.VerifyAll = Args.hasArg(OPT_sil_verify_all);
   Opts.PrintAll = Args.hasArg(OPT_sil_print_all);
+  Opts.TimeTransforms = Args.hasArg(OPT_sil_time_transforms);
 
   return false;
 }