serial/arc-uart: platform_data order changed

* is_emulated is now 1st element, rather than last
* also tucked all platform data refs together

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: linux-serial@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>