The implementation of Flatten() Torque generates for CSA struct types
and the current implementation of EmitCCValue make heavy use of
std::make_tuple and std::tuple_cat, which had a noticeable impact on
build times of generated files including these outputs.
This CL eliminates all uses of std::tuple_cat and most uses of
std::make_tuple.

Bug: v8:9861
Change-Id: Ib950b2c87983171b8c32c388fc115d2407087717
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2784563
Commit-Queue: Nico Hartmann <nicohartmann@chromium.org>
Reviewed-by: Seth Brenith <seth.brenith@microsoft.com>
Cr-Commit-Position: refs/heads/master@{#73660}