iio: 104-quad-8: Fix off-by-one error when addressing flag register
The flag register is offset by 1 from the respective channel data
register. This patch fixes an off-by-one error when attempting to read a
channel flag register where the base address was not properly offset.
Fixes: 28e5d3bb0325 ("iio: 104-quad-8: Add IIO support for the ACCES 104-QUAD-8") Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>