OMAP1: Amstrad Delta: add camera controlled LEDS trigger

This patch extends the Amstrad Delta camera support with LEDS trigger that can
be used for automatic control of the on-board camera LED. The led turns on
automatically on camera device open and turns off on camera device close.

Signed-off-by: Janusz Krzysztofik <jkrzyszt@tis.icnet.pl>
Signed-off-by: Tony Lindgren <tony@atomide.com>