onenand: fix oob print out issue

Seems original implementation forget to set the pointer to point
to the oobbuf, so when we want to see oob buf, we see nothing...
Fix it by get pointer as the oobbuf set.

Signed-off-by: Lei Wen <leiwen@marvell.com>
diff --git a/common/cmd_onenand.c b/common/cmd_onenand.c
index 33108f1..cb2ba70 100644
--- a/common/cmd_onenand.c
+++ b/common/cmd_onenand.c
@@ -293,7 +293,7 @@
 	addr = (loff_t) off;
 	memset(&ops, 0, sizeof(ops));
 	ops.datbuf = datbuf;
-	ops.oobbuf = oobbuf; /* must exist, but oob data will be appended to ops.datbuf */
+	ops.oobbuf = oobbuf;
 	ops.len = mtd->writesize;
 	ops.ooblen = mtd->oobsize;
 	ops.retlen = 0;
@@ -319,6 +319,8 @@
 	}
 	puts("OOB:\n");
 	i = mtd->oobsize >> 3;
+	p = oobbuf;
+
 	while (i--) {
 		printf("\t%02x %02x %02x %02x %02x %02x %02x %02x\n",
 		       p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7]);