[superproject] Roll scudo [scudo] Compute the default aligned pointer…

… without tag (#92989)

llvm/llvm-project#83493 slightly
changed the order of computation of block addresses and
pointers, causing the value of DefaultAlignedPtr to
include the MTE tag. Move this computation earlier so it
matches the old behavior.

This fixes a UBSan failure in Trusty:
secure os: UBSan: (overflow:-)
external/scudo/standalone/combined.h:1070:35
secure os: Details: unsigned integer overflow: 8988807738704 -
144124176883594576 cannot be represented in type 'uptr'

GitOrigin-RevId: 68d65af99a063e79222c790f5afcdcf2e58b38db
Original-Revision: 01bc3bce33d2f804df1828387577bef23fbd8c7d
Roller-URL: https://ci.chromium.org/b/8747120831581303473
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: I78b348eeae725db1367d1580aec2d1e21e5550d0
Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/1053852