ns16550.c: Fix for ns16550 driver hanging on OMAP4

The same problem that is seen on some OMAP3 is also seen on some OMAP4
so include them in the test in order to prevent some hangs during SPL.

[trini: Re-word commit message, make apply cleanly]
Signed-off-by: Tom Rini <trini@ti.com>

drivers/serial/ns16550.c

@@ -132,11 +132,12 @@ static void NS16550_setbrg(NS16550_t com_port, int baud_divisor)
 
 void NS16550_init(NS16550_t com_port, int baud_divisor)
 {
-#if (defined(CONFIG_SPL_BUILD) && defined(CONFIG_OMAP34XX))
+#if (defined(CONFIG_SPL_BUILD) && \
+		(defined(CONFIG_OMAP34XX) || defined(CONFIG_OMAP44XX)))
 	/*
-	 * On some OMAP3 devices when UART3 is configured for boot mode before
-	 * SPL starts only THRE bit is set. We have to empty the transmitter
-	 * before initialization starts.
+	 * On some OMAP3/OMAP4 devices when UART3 is configured for boot mode
+	 * before SPL starts only THRE bit is set. We have to empty the
+	 * transmitter before initialization starts.
 	 */
 	if ((serial_in(&com_port->lsr) & (UART_LSR_TEMT | UART_LSR_THRE))
 	     == UART_LSR_THRE) {