Please rebuild all ports that depend on PNG

[b. f.]

> > Realy no other possibility?!
>
> You need to rebuild all the ports that install binaries that link
> against libpngNN.so.NN.  That is actually a subset of the ports that
> depend on graphics/png -- unfortunately it takes some effort to identify
> precisely what does need rebuilding.  There is the pkg_libchk script
> (which is part of sysutils/bsdadminscripts) that can help.
...
> Use pkg_libchk to prioritise the ports that really need to be rebuilt.

Lawrence Stewart's convenient script can be used with portmaster to
perform this kind of update:

https://lauren.room52.net/hg/scripts/raw-file/tip/libdepend/libdepend.sh

b.