TPS65911 adds new interrupt sources, as well as two new registers
to handle them, one for interrupt status and one for interrupt
masking. The added irqs are:

-VMBCH2 - Low and High threshold
-GPIO1-8 - Rising and falling edge detection
-WTCHDG - Watchdog interrupt
-PWRDN	- PWRDN reset interrupt

The code should handle these new registers only when the chip
version is TPS65911.
Signed-off-by: NJorge Eduardo Candelaria <jedu@slimlogic.co.uk>
Acked-by: NSamuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NLiam Girdwood <lrg@slimlogic.co.uk>