omap3: 3630sdp: Explicitly enable all UARTs

All UARTs seem physically reachable, so, enable them all.
Signed-off-by: Sergio Aguirre <saaguirre@ti.com>

arch/arm/mach-omap2/board-3630sdp.c

@@ -96,6 +96,7 @@ static struct omap_board_mux board_mux[] __initdata = {
 static void __init omap_sdp_init(void)
 {
 	omap3_mux_init(board_mux, OMAP_PACKAGE_CBP);
+	omap_serial_init();
 	zoom_peripherals_init();
 	board_smc91x_init();
 	enable_board_wakeup_source();