CHROMIUM: mfd: chromeos_ec: Fix __devexit annotation on cros_ec_free

CHROMIUM: mfd: chromeos_ec: Fix __devexit annotation on cros_ec_free

cros_ec_free can be called from cros_ec_probe_i2c so should not have the
__devexit annotation.  This fixed the section mismatch warning.

BUG=None
TEST=Built kernel, verified no section mismatch warning.
  Booted kernel, no obvious regressions
Signed-off-by: Jonathan Kliegman <kliegs@chromium.org>
Change-Id: Ie9b13c73dbe881c368ae5daec8caf32b316294ce
Reviewed-on: https://gerrit.chromium.org/gerrit/34435
Tested-by: Jon Kliegman <kliegs@chromium.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
Commit-Ready: Jon Kliegman <kliegs@chromium.org>