serial: 8250: 8250_omap: make a const array static, makes object smaller

Don't populate the const array k3_soc_devices on the stack but instead it
static. Makes the object code smaller by 44 bytes:

Before:
   text    data     bss     dec     hex filename
  31628    5609     128   37365    91f5 drivers/tty/serial/8250/8250_omap.o

After:
   text    data     bss     dec     hex filename
  31520    5673     128   37321    91c9 drivers/tty/serial/8250/8250_omap.o
Reduction of 44 bytes

(gcc version 10.3.0)
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: https://lore.kernel.org/r/20210715140759.27244-1-colin.king@canonical.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/8250/8250_omap.c

@@ -538,7 +538,7 @@ static void omap_8250_pm(struct uart_port *port, unsigned int state,
 static void omap_serial_fill_features_erratas(struct uart_8250_port *up,
 					      struct omap8250_priv *priv)
 {
-	const struct soc_device_attribute k3_soc_devices[] = {
+	static const struct soc_device_attribute k3_soc_devices[] = {
 		{ .family = "AM65X",  },
 		{ .family = "J721E", .revision = "SR1.0" },
 		{ /* sentinel */ }