IIO fixes for 4.0 set 4

A couple more IIO fixes.

* Fix check for HAS_IOMEM in the cc100001_adc driver to avoid build errors.
  Rather curiously it was ORed with Regulator and clock support.
* vf610 driver was trying to use an ADC clock outside the possible
  spec on some boards.  The driver assumed a fixed clock speed previously
  across all boards, but that is not true.  This fix ensures that the
  reported frequency is correct on all boards.
* The adis imu common code directly set the current trigger to the
  driver supplied one.  Unfortunately this didn't increase the use count
  leading to a double free via a particular path of changing the trigger
  then removing the driver.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2
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=BbAz
-----END PGP SIGNATURE-----