iio_readdev: Allow to specify the number of samples to capture
iio_readdev: Allow to specify the number of samples to capture

Currently iio_readdev will capture samples until it is stopped. This patch
adds a option that allows to specify the number of samples that should be
capture. Once the specified number of samples has been captured iio_readdev
will stop automatically.

Signed-off-by: Lars-Peter Clausen <3318dc5ce3e4fb7c28a0b841b6801c884e1d0896@metafoo.de>

analogdevicesinc/libiio,gburca/libiio,analogdevicesinc/libiio,analogdevicesinc/libiio,Sunderfield/libiio,Sunderfield/libiio,sensarliar/libiio,analogdevicesinc/libiio,sensarliar/libiio,gburca/libiio,sensarliar/libiio,gburca/libiio,Sunderfield/libiio