serial: sh-sci: disable callback typo fix

Avoid invoking the disable callback in case of NULL.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/drivers/serial/sh-sci.c b/drivers/serial/sh-sci.c
index 85119fb..6498bd1 100644
--- a/drivers/serial/sh-sci.c
+++ b/drivers/serial/sh-sci.c
@@ -1143,7 +1143,7 @@
 	while ((sci_in(port, SCxSR) & bits) != bits)
 		cpu_relax();
 
-	if (sci_port->disable);
+	if (sci_port->disable)
 		sci_port->disable(port);
 }