Log message:
Update to 0.58

Upstream changes:
0.58: Nov 25, 2018

   - on inflate error, first return any remaining bytes before returning the error.

   - remove leading "./" even if ac->currentDir[] is not set; \ 
change mirrors a
     change in rsync-bpc and has no effect here since BackupPC::XS doesn't set
     ac->currentDir[].

   - bpc_attrib_dirWrite() updates dir->digest with new digest.

   - updated configure.sh with package name and current version

Log message:
sysutils/p5-BackupPC-XS: import p5-BackupPC-XS-0.57

BackupPC::XS implements various BackupPC functions in a perl-callable
module. This module is required by sysutils/backuppc>=4.0.