mx23evk: Add initial board support

The following features are supported:
 * 128 MB DDR1 SDRAM
 * DUART
 * SD/MMC Card Socket

Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
Tested-by: Fabio Estevam <fabio.estevam@freescale.com>
diff --git a/MAINTAINERS b/MAINTAINERS
index dfa3c8b..faa9b5e 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -947,6 +947,10 @@
 
 	ca9x4_ct_vxp	ARM ARMV7 (Quad Core)
 
+Otavio Salvador <otavio@ossystems.com.br>
+
+	mx23evk		i.MX23
+
 Prafulla Wadaskar <prafulla@marvell.com>
 
 	aspenite	ARM926EJS (ARMADA100 88AP168 SoC)