staging: iio: accel: remove else after return

This patch fixes checkpatch.pl warning in files of iio: accel
WARNING : else is not generally useful after a break or return

Signed-off-by: Tapasweni Pathak <tapaswenipathak@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>