Revert 3c4fd2463bb2 since upstream libcxxrt fixed it in another way
In 0ee0dbfb0d26cf4bc37f24f12e76c7f532b0f368 I imported a more recent
libcxxrt snapshot, which includes an upstream fix for the padding of
However, we also had a similar fix in our tree as:
Since having both fixes makes the struct too large again, it leads to
SIGBUSes when throwing exceptions on amd64 (or other LP64 arches). This
is most easily tested by running kyua without any arguments.
It looks like our fix is no longer needed now, so revert it to reduce
diffs against upstream.