iio: gyro: fxas21002c: balance runtime power in error path

If we fail to read temperature or axis we need to decrement the
runtime pm reference count to trigger autosuspend.

Add the call to pm_put to do that in case of error.

Fixes: a0701b62 ("iio: gyro: add core driver for fxas21002c")
Suggested-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Rui Miguel Silva <rui.silva@linaro.org>
Link: https://lore.kernel.org/linux-iio/CBBZA9T1OY9C.2611WSV49DV2G@arch-thunder/


Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>