ttydev: fix pamc_zilog for tty pointer move

Today's linux-next build (sparc64 defconfig) failed like this:

drivers/serial/sunhv.c: In function `receive_chars':
drivers/serial/sunhv.c:188: error: structure has no member named `tty'
drivers/serial/sunsu.c: In function `receive_chars':
drivers/serial/sunsu.c:314: error: structure has no member named `tty'
drivers/serial/sunsab.c: In function `receive_chars':
drivers/serial/sunsab.c:121: error: structure has no member named `tty'

I applied the following patch (which, again, may not be correct).

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/serial/sunsab.c b/drivers/serial/sunsab.c
index 9ff5b38..15ee497 100644
--- a/drivers/serial/sunsab.c
+++ b/drivers/serial/sunsab.c
@@ -118,7 +118,7 @@
 	int i;
 
 	if (up->port.info != NULL)		/* Unopened serial console */
-		tty = up->port.info->tty;
+		tty = up->port.info->port.tty;
 
 	/* Read number of BYTES (Character + Status) available. */
 	if (stat->sreg.isr0 & SAB82532_ISR0_RPF) {