Log Message:
perl5: remove workaround for /self/proc/exe being '/'

The patch is from 2008, and according to martin@ on current-users@,
the problem was fixed in 2007 in sys/miscfs/procfs/procfs_vnops.c
rev 1.152). If the problem is still there, please file a NetBSD bug
report.

Bump PKGREVISION.