CI/travis/deploy: use libiio's upload_file_to_swdownloads() function
CI/travis/deploy: use libiio's upload_file_to_swdownloads() function

The entire logic of that function should now be usable here.

Signed-off-by: Alexandru Ardelean <685557f6b7c225d86b536740313ed51b24843a58@analog.com>

analogdevicesinc/libad9361-iio,analogdevicesinc/libad9361-iio,analogdevicesinc/libad9361-iio,analogdevicesinc/libad9361-iio