4.6.1 25 MAR 2023 Bug fix release to fix race condition and XATTRs
code
1. Race condition which can cause corruption of the "fragment table"
fixed. This is a regression introduced in August 2022, and it has
been seen when tailend packing is used (-tailends option).
2. Fix build failure when the tools are being built without extended
attribute (XATTRs) support.
3. Fix XATTR error message when an unrecognised prefix is found
(Christian Hesse).
4. Fix incorrect free of pointer when an unrecognised XATTR prefix is
found.
