Use the classical way of removing applications and then make sure to remove the .app files in the following locations:
./Library/Application Support/Motorola Mobility/MotoHelper.app/Contents/Resources/DeviceSoftwareUpdate.app
./Library/Application Support/Motorola Mobility/MotoHelper.app/Contents/Resources/MDMUpdater.app
./Library/Application Support/Motorola Mobility/MotoHelper.app/Contents/Resources/MotoHelperAgent.app
And just like in Windows, once you removed these, reboot the PC, reinstall the app and repeat the removing procedure to fully get rid of the app in case something is still on your Mac.