Merge tag 'iio-for-3.13b' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next

Jonathan writes:

Second set of new functionality for IIO in the 3.13 cycle - with bug fixes for first set.

This is a small, mainly to get a couple of compile bug related fixes into
the tree ASAP.

New device support:
1) Add ad5446 dac support to the ad5641 driver.

New functionality and cleanups:
1) Optional power supply regulators for the st pressure sensors drivers using
   the new optional regulator interface.
2) Bit of tidying up of naming in the sysfs trigger.

Bug fixes from the previous series:
1) Missing select IIO_BUFFER for ti_am335x_adc
2) Drop a bonus bracket in iio-trig-bfin-timmer