The actual fix as been done by "pkglint -F */*/buildlink3.mk", and was
reviewed manually.
There are some .include lines that still are indented with zero spaces
although the surrounding .if is indented. This is existing practice.
librsync implements the rolling-checksum algorithm of remote
file synchronization that was popularized by the rsync utility. This
algorithm transfers the differences between 2 files without needing both
files on the same system. librsync is for building other programs that
transfer files as efficiently as rsync. You can use librsync in a program
you write to do backups, distribute binary patches to programs, or
sync directories to a server or between peers.