bzip2 does not exit after showing license as requested with --version

bzip2 does not exit after showing license as requested with --version
or --license as most apps would do, instead it waits for data to
compress on stdin. Because of that, if `bzip2 --version' is called,
bogus `bzip2: I won't write compressed data to a terminal' error
message will be displayed, and checking for bzip2 version in scripts
as in

    bzip2 --version 2>&1 | grep -o "Version [^,]*"

will hand as bzip2 would wait for data to compress on stdin. Fix
this by exiting right after showing version/license text.

I've tried to push this upstream for more than a year, but author
is unresponsive, so upstream may be considered dead.

Ubuntu applies similar fix, for the note.

PR:		199443
Approved by:	dim, bapt
MFC after:	2 weeks
Differential Revision:	D8924