iio get rid of unneccessary error_ret

Get rid of obsolete uses of goto error_ret and some empty lines.

Signed-off-by: Hartmut Knaack <knaack.h@gmx.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

diff --cc drivers/iio/buffer_cb.c
Simple merge

diff --cc drivers/iio/industrialio-buffer.c
Simple merge

diff --cc drivers/iio/industrialio-core.c
Simple merge

diff --cc drivers/iio/industrialio-event.c
Simple merge

diff --cc drivers/iio/industrialio-trigger.c
Simple merge