mxs: Add MX23 olinuxino board support

This patch adds support for MX23-based Olinuxino board.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Fabio Estevam <fabio.estevam@freescale.com>
Cc: Otavio Salvador <otavio@ossystems.com.br>
Cc: Stefano Babic <sbabic@denx.de>
diff --git a/MAINTAINERS b/MAINTAINERS
index 28c052d..dfa3c8b 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -935,6 +935,7 @@
 	palmtc		xscale/pxa
 	vpac270		xscale/pxa
 	zipitz2		xscale/pxa
+	mx23_olinuxino	i.MX23
 	m28evk		i.MX28
 	sc_sps_1	i.MX28