Nokia RX-51: Fix checking if serial console was enabled

There was incorrect logic for parsing OMAP_TAG_UART atag.

Signed-off-by: Pali Rohár <pali@kernel.org>
diff --git a/board/nokia/rx51/rx51.c b/board/nokia/rx51/rx51.c
index 60a2e36..93d1b2f 100644
--- a/board/nokia/rx51/rx51.c
+++ b/board/nokia/rx51/rx51.c
@@ -146,7 +146,7 @@
 			}
 			break;
 		case OMAP_TAG_UART:
-			if (!t->u.uart.enabled_uarts)
+			if (t->u.uart.enabled_uarts)
 				serial_was_console_enabled = 1;
 			break;
 		case OMAP_TAG_SERIAL_CONSOLE: