synclink_gt: leave transmitter in reset state after configuration

Leave the transmitter in reset state after configuration so that transmit
signal is held at mark until transmitter is explicitly enabled by
application, otherwise transmitter sends idle pattern.

Signed-off-by: Paul Fulghum <paulkf@microgate.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>