/usr/lib/qlandkartegt/libGPSMap76CS.so is in qlandkartegt-garmin 0.3.4+svn3432-2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/qlandkartegt/libEtrexLegendC.so
/usr/lib/qlandkartegt/libEtrexLegendC.so