davinci: DA830/OMAP-L137 EVM: fix warning with default config

This patch fixes the following warning seen when building with default
config:

arch/arm/mach-davinci/board-da830-evm.c:371: warning: 'da830_evm_devices' defined but not used

Tested on DA830 EVM with and without CONFIG_DA830_UI_NAND enabled.

Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>