iio: 104-quad-8: Fix off-by-one error in register selection

The reset flags operation is selected by bit 2 in the "Reset and Load
Signals Decoders" register, not bit 1.

Fixes: 28e5d3bb ("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 <Jonathan.Cameron@huawei.com>