databases/xtrabackup: Update to 2.4.9
Port changes:
* Change to DISTVERSION
* Add the specific boost version to fix build
* Add curl to LIB_DEPENDS
* Move bison from BUILD_DEPENDS to USES=bison
* Add/delete patches
PR: 216870
Submitted by: samm@os2.kiev.ua
Approved by: Aleksandr Kuzminsky <aleks@twindb.com> (maintainer)