update rotors_hil.rosintall to clone mavros upstream master

Author: TSC21

rotors_hil.rosinstall

@@ -1,4 +1,4 @@
 - git: {local-name: mav_comm, uri: 'https://github.com/ethz-asl/mav_comm.git'}
 - git: {local-name: mavlink, uri: 'https://github.com/mavlink/mavlink-gbp-release.git', version: 'upstream'}
-- git: {local-name: mavros, uri: 'https://github.com/ethz-asl/mavros.git'}
+- git: {local-name: mavros, uri: 'https://github.com/mavlink/mavros.git'}
 - git: {local-name: rotors_simulator, uri: 'https://github.com/ethz-asl/rotors_simulator.git'}