The patch adds following configurations to enable build of mx23evk
and mx28evk in defconfig.

  CONFIG_MACH_MX23EVK
  CONFIG_MACH_MX28EVK
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NSascha Hauer <s.hauer@pengutronix.de>

The patch fixes the warning below.

arch/arm/configs/mxs_defconfig:92:warning: symbol value 'm' invalid for RTC_CLASS
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NSascha Hauer <s.hauer@pengutronix.de>

Covers MX23, MX28 and STMP378x.
Signed-off-by: NWolfram Sang <w.sang@pengutronix.de>
Cc: Shawn Guo <shawn.guo@freescale.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>