arm: vf610: Add Vybrid VF610 to mxc_ocotp document

This patch adds Vybrid VF610 to mxc_ocotp document.

Signed-off-by: Alison Wang <b18965@freescale.com>
Reviewed-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
diff --git a/doc/README.mxc_ocotp b/doc/README.mxc_ocotp
index 9a53311..7a2863c 100644
--- a/doc/README.mxc_ocotp
+++ b/doc/README.mxc_ocotp
@@ -2,6 +2,7 @@
 on MXC
 
 This IP can be found on the following SoCs:
+ - Vybrid VF610,
  - i.MX6.
 
 Note that this IP is different from albeit similar to the IPs of the same name