error: Clean up error strings with embedded newlines

The arguments of error_report() should yield a short error string
without newlines.

A few places try to print additional help after the error message by
embedding newlines in the error string.  That's nice, but let's do it
the right way.

Since I'm touching these lines anyway, drop a stray preposition and
some tabs.  We don't use tabs for similar messages elsewhere.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-id: 1360354939-10994-2-git-send-email-armbru@redhat.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>