pm2301-charger: Wake device on register access

When USB  Dedicated or Standard host chargers are plugged into
the device, chargealg attempts to disable the PM2301 AC charger,
However, disabling PM2301 was failing because of it being in
runtime suepend mode & LPN pin being low.

Signed-off-by: Rupesh Kumar <rupesh.kumar@stericsson.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Reviewed-by: Marcus COOPER <marcus.xm.cooper@stericsson.com>
Reviewed-by: Philippe LANGLAIS <philippe.langlais@stericsson.com>