uboot-imx

kbuild,mxs: use short logs for MXS images

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Cc: Fabio Estevam <fabio.estevam@freescale.com>
Cc: Otavio Salvador <otavio@ossystems.com.br>
Cc: Lauri Hintsala <lauri.hintsala@bluegiga.com>
Acked-by: Marek Vasut <marex@denx.de>