clk: davinci: psc-da830: add a lookup entry for aemif clock

We want to use the ti-aemif platform driver for da830-evm. To make it
work we need a lookup entry for the aemif clock.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: David Lechner <david@lechnology.com>
Signed-off-by: David Lechner <david@lechnology.com>