This reverts commit f97f7d79.

Reason for revert: a simpler approach will be used instead.

Original change's description:
> [ptr-compr-8gb] Align Turbofan allocations to 8 bytes
>
> In order to support a larger heap cage (8GB, 16GB), the cage offset
> will take up more than 32 bits. As a consequence, for 8GB cages, the
> least significant bit of the cage offset will overlap with the most
> significant bit of the tagged offset. To avoid this, allocations need
> to be aligned to 8 bytes to free up one bit from the offset.
>
> All changes are deactivated behind the build flag
> `v8_enable_pointer_compression_8gb`. Allocation folding is not yet
> supported.
>
> Bug: v8:13070
> Change-Id: I602c71232e98eac4e2701b0922704a7adc31a662
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3817741
> Commit-Queue: Teo Dutu <teodutu@google.com>
> Reviewed-by: Marja Hölttä <marja@chromium.org>
> Reviewed-by: Igor Sheludko <ishell@chromium.org>
> Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#82331}

Bug: v8:13070
Change-Id: Id2186898596847142a80aba7604e870093a26d8b
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3879224Reviewed-by: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Nico Hartmann <nicohartmann@chromium.org>
Commit-Queue: Teo Dutu <teodutu@google.com>
Cr-Commit-Position: refs/heads/main@{#83071}