When pntr compression is enabled, `Pointer()` reads 8 bytes
whereas `TaggedPointer()` reads 4 bytes and decompresses.

TaggedPointer() in this case was causing an incorrect read
on big endian as the desired value was located on the high side
of memory.

Similar patches were also applied in this CL:
https://crrev.com/c/2057355

Change-Id: I77c449256ae1f56f2f8664f687985221badf819f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3314302
Commit-Queue: Milad Farazmand <mfarazma@redhat.com>
Reviewed-by: Manos Koukoutos <manoskouk@chromium.org>
Cr-Commit-Position: refs/heads/main@{#78232}