ARM: SAMSUNG: Fix UART number for S5P6442

The recent changes in the UART code mean that we need to ensure that
the 4 UART case is only selected if S5PV210 is being compiled.
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

drivers/serial/Kconfig

@@ -552,7 +552,7 @@ config SERIAL_S5PC100
 config SERIAL_S5PV210
 	tristate "Samsung S5PV210 Serial port support"
 	depends on SERIAL_SAMSUNG && (CPU_S5PV210 || CPU_S5P6442)
-	select SERIAL_SAMSUNG_UARTS_4
+	select SERIAL_SAMSUNG_UARTS_4 if CPU_S5PV210
 	default y
 	help
 	  Serial port support for Samsung's S5P Family of SoC's