travis.yml: use different swig ppa for Travis CI builds
travis.yml: use different swig ppa for Travis CI builds

Signed-off-by: Mihai Tudor Panu <a27de6130c5d32f5817bf40bb8b348582f37a8af@intel.com>

intel-iot-devkit/upm,g-vidal/upm,stefan-andritoiu/upm,intel-iot-devkit/upm,intel-iot-devkit/upm,jontrulson/upm,sasmita/upm,intel-iot-devkit/upm,nitirohilla/upm,jontrulson/upm,stefan-andritoiu/upm,malikabhi05/upm,intel-iot-devkit/upm,whbruce/upm,pylbert/upm,g-vidal/upm,skiselev/upm,skiselev/upm,whbruce/upm,spitfire88/upm,Propanu/upm,Jon-ICS/upm,g-vidal/upm,sasmita/upm,spitfire88/upm,stefan-andritoiu/upm,Propanu/upm,g-vidal/upm,spitfire88/upm,Propanu/upm,nitirohilla/upm,skiselev/upm,nitirohilla/upm,whbruce/upm,skiselev/upm,nitirohilla/upm,skiselev/upm,jontrulson/upm,stefan-andritoiu/upm,sasmita/upm,Jon-ICS/upm,malikabhi05/upm,sasmita/upm,malikabhi05/upm,stefan-andritoiu/upm,g-vidal/upm,pylbert/upm,malikabhi05/upm,stefan-andritoiu/upm,sasmita/upm,pylbert/upm,Jon-ICS/upm,g-vidal/upm,intel-iot-devkit/upm,jontrulson/upm,spitfire88/upm,pylbert/upm,Propanu/upm,whbruce/upm,Jon-ICS/upm,whbruce/upm,Propanu/upm,malikabhi05/upm,pylbert/upm,malikabhi05/upm,Jon-ICS/upm,jontrulson/upm,Propanu/upm,skiselev/upm,spitfire88/upm,pylbert/upm,nitirohilla/upm