iio: {ad_,cf_axi_}*: Cleanup probe and remove functions

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
iio: cf_axi_dds: Fix missing unlock on error path

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
iio: kfifo: Fix double unlock

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
iio: ad9517: Fix out of bounds access

AD9517_TRANSFER is the last register, so the array needs to be AD9517_TRANSFER +
1 elements large.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
iio: ad9523: Fix potential buffer overflow

The maximum number of characters to copy should obviously be the size of the
destination buffer, not the size of the source buffer. Also use strlcpy to make
sure that the string is zero terminated.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>