MLK-21861 mx7dsabresd: Fix wrong gpio name for io expander

Since the io expander node in DTS is using name gpio-expander not gpio_spi,
must update the codes for the name, otherwise fec initialization will hang.

Signed-off-by: Ye Li <ye.li@nxp.com>
diff --git a/board/freescale/mx7dsabresd/mx7dsabresd.c b/board/freescale/mx7dsabresd/mx7dsabresd.c
index b3212c2..04c6086 100644
--- a/board/freescale/mx7dsabresd/mx7dsabresd.c
+++ b/board/freescale/mx7dsabresd/mx7dsabresd.c
@@ -262,9 +262,9 @@
 	int ret;
 	unsigned int gpio;
 
-	ret = gpio_lookup_name("gpio_spi@0_5", NULL, NULL, &gpio);
+	ret = gpio_lookup_name("gpio-expander@0_5", NULL, NULL, &gpio);
 	if (ret) {
-		printf("GPIO: 'gpio_spi@0_5' not found\n");
+		printf("GPIO: 'gpio-expander@0_5' not found\n");
 		return -ENODEV;
 	}