mfd: Optimised twl4030-power power scripts for the rx51

The power scripts optimisation was mainly done by:
Tero Kristo <tero.kristo@nokia.com> and
Arnaud Mandy <ext-arnaud.2.mandy@nokia.com>

I'm only refactoring and testing it against the mainline kernel.

Signed-off-by: Amit Kucheria <amit.kucheria@verdurent.com>
Cc: Tero Kristo <tero.kristo@nokia.com>
Cc: linux-omap@vger.kernel.org
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>