mcx: support for HTKW mcx board

This patch adds support for the HTKW mcx AM3517-based board.
Serial, Ethernet, NAND, MMC, RTC, EHCI USB host and both
NAND and MMC SPLs are supported.

Signed-off-by: Ilya Yanok <yanok@emcraft.com>
Signed-off-by: Stefano Babic <sbabic@denx.de>
CC: Tom Rini <tom.rini@gmail.com>
Cc: Detlev Zundel <dzu@denx.de>
Acked-by: Igor Grinberg <grinberg@compulab.co.il>
diff --git a/boards.cfg b/boards.cfg
index f83e954..ceaf9ac 100644
--- a/boards.cfg
+++ b/boards.cfg
@@ -219,6 +219,7 @@
 omap3_evm_quick_nand         arm         armv7       evm                 ti             omap3
 omap3_sdp3430                arm         armv7       sdp3430             ti             omap3
 devkit8000                   arm         armv7       devkit8000          timll          omap3
+mcx                          arm         armv7       mcx                 htkw           omap3
 tricorder                    arm         armv7       tricorder           corscience     omap3
 twister                      arm         armv7       twister             technexion     omap3
 omap4_panda                  arm         armv7       panda               ti             omap4