Revert "kfmt: fix bug where calls to copy() resulted in garbage being copied"
Revert "kfmt: fix bug where calls to copy() resulted in garbage being copied"

This reverts commit 8f04deadc1f1620dbd0aaea07f04a6c7f82f58c0.

The actual issue was triggered by a memory corruption due to the fact
that the exception handling gate code did not preserve XMM regs.

achilleasa/gopher-os,achilleasa/gopher-os