davinci: omapl138_lcdk: remove spiboot

OMAP-L138 LCDK board does not have a SPI flash.
Remove spiboot related environment variable
definitions.

Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Reviewed-by: Lukasz Majewski <lukma@denx.de>
Reviewed-by: Tom Rini <trini@konsulko.com>
1 file changed