[PATCH] Don't disable irqs in set_next_event and set_mode callbacks

[Alessandro Rubini]

> Nomadik only works because it doesn't support periodic mode.

s/periodic/one-shot/

Uwe, I can't test it as my board is currently unavailable, but I have
no problems in removing the irqsave stuff if not needed. Actually,
I use the atmel code as a reference, so I got the irqsave from there.

Feel free to add my acked-by if you think it's worth.

/alessandro