USB: s3c: Enable soft disconnect during initialization

Enable soft disconnect bit the OTG core during initialization. Without this,
the host sees that a gadget is connected and tries to enumerate. The
soft disconnect should be enabled until the USB gadget driver is
registered with this otg driver.

Signed-off-by: Thomas Abraham <thomas.ab@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>