ARM: mxs: Rename M28EVK

The board is now manufactured by Aries Embedded GmbH , rename it.

Signed-off-by: Marek Vasut <marex@denx.de>
diff --git a/doc/README.mxs b/doc/README.mxs
index 4edf19f..e23ab9c 100644
--- a/doc/README.mxs
+++ b/doc/README.mxs
@@ -95,7 +95,7 @@
 
 Examples:
 
-1. For building U-Boot for Denx M28EVK board:
+1. For building U-Boot for Aries M28EVK board:
 
 	$ make m28evk_config