Fix gnss replay

Change the /dev/gnss0 read logic, will send the  CMD_GET_LOCATION to
/dev/gnss0 first.
launch_cvd   --start_gnss_proxy --gnss_file_path=xxx

Test: Manually

Change-Id: Ic493790e80ceb6fd4d890b31e596b5c08addee40
3 files changed