Ruby

• internal.h (struct rb_execarg) moved and renamed from
  struct rb_exec_arg in intern.h.

• include/ruby/intern.h (struct rb_exec_arg): refer Data object which
  contains struct rb_execarg.

• process.c: use struct rb_execarg instead of struct rb_exec_arg
  except functions declared in intern.h.
  (rb_exec_arg_addopt): extract a pointer to struct rb_execarg from
  struct rb_exec_arg.
  (rb_exec_arg_init): ditto.
  (rb_exec_arg_fixup): ditto.
  (rb_run_exec_options_err): ditto.
  (rb_run_exec_options): ditto.
  (rb_exec_err): ditto.
  (rb_exec): ditto.

• io.c: use struct rb_execarg instead of struct rb_exec_arg.

• ext/pty/pty.c: ditto.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@36153 b2dd03c8-39d4-4d8f-98ff-823fe69b080e