travis : Add the LDIST for centos
travis : Add the LDIST for centos

Currenty - when travis-ci builds for centos, the LDIST is set to trusty, so things get deployed with the trusty namespace. Fix that.

Signed-off-by: Robin Getz <3da152ba4202edb75e09c38bdf5deacc763a02bb@analog.com>
analogdevicesinc/libiio,analogdevicesinc/libiio,analogdevicesinc/libiio,analogdevicesinc/libiio