davinci: INTC: add support for TI cp_intc

Add support for Texas Instuments Common Platform Interrupt Controller
(cp_intc) used on DA830/OMAP-L137.

Signed-off-by: Steve Chen <schen@mvista.com>
Signed-off-by: Mark Greer <mgreer@mvista.com>
Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>