pxa270 powersaving

Some days ago I made a driver (named pxa270-voltage) to set cpu core voltage according to its frequency, it should improve battery life (but I did not perform testing). freq-voltage table was taken from cpufreq-2xx driver. If anyone can test and report if it really improves battery life - it would be nice.

Here's new patchset, precompiled binaries can be taken here, patches still should be applied ontop of Marex's tree

Also new patchset fixes race condition in pxa2xx-spi suspend handler.

P.S. This driver is just temporary solution until someone fix cpufreq on pxa270.

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