libmultipath: fix tur memory misuse

libmultipath: fix tur memory misuse

when tur_thread() was calling tur_check(), it was passing ct->message as
the copy argument, but copy_msg_to_tcc() was assuming that it was
getting a tur_checker_context pointer. This means it was treating
ct->message as ct. This is why the tur checker never printed checker
messages. Intead of simply changing the copy argument passed in, I just
removed all the copying code, since it is completely unnecessary. The
callers of tur_check() can just pass in a buffer that it is safe to
write to, and copy it later, if necessary.

Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>