all: further adjustments for new Ronna, Quetta SI prefixes

all: further adjustments for new Ronna, Quetta SI prefixes

* src/dd.c (parse_integer): Support Q,R suffixes.
* src/od.c (main): Likewise.
* src/split.c (main): Likewise.
* src/stdbuf.c (parse_size): Likewise.
* src/truncate.c (main): Likewise.
* src/sort.c (specify_size_size): Likewise.
Also line length syntax check fix.
* tests/misc/numfmt.pl: Adust top end large number checks
to the new largest values.
* doc/coreutils.texi (numfmt invocation): Add a numfmt example.
* NEWS: Tweak to aid searchability.