Log the switch value when reaching an UNREACHABLE().

Bug 20025568

Change-Id: I37d2c7171e0704b4064e56e8ca8799f930038d87
Reviewed-on: https://swiftshader-review.googlesource.com/3481
Reviewed-by: Nicolas Capens <capn@google.com>
Tested-by: Nicolas Capens <capn@google.com>
52 files changed