Log Message:
Update xentools415 and xenstoretools to 4.15.3.
pkgsrc changes: drop egg.mk from xentools415 (it's not suitable for this
package and causes duplicate targets); and instead mark as incompatible
with python2.7 and TOOL_DEPEND on py-setuptool.
See http://mail-index.netbsd.org/tech-pkg/2022/07/04/msg026500.html
and followups for details

Upstream changes are mostly bugfixes