iputils: update to 20210202

iputils: update to 20210202

The changelog between version "s20160803" is too large to include it
here, please refer to https://github.com/iputils/iputils/releases for a
human-readable version.

Due to build system changes, single binaries cannot be compiled by
running "make [program]" anymore, updated rootfiles to reflect that
change.

20210202's version of /usr/bin/ping is bug-compatible to s20160803's
one, hence does not cause trouble in ~/src/ppp/ip-up. Tested, works.

Signed-off-by: Peter Müller <peter.mueller@ipfire.org>
Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>