[Linux] Incorrect name of icon for desktop entries

Description:
cursor.desktop of AppImage needs Icon=co.anysphere.cursor.
But usr/share/icons/hicolor/22x22/apps/corsor.png is provided. It is unused (at least for extracted image).

Moreover, it would be nice if files at usr/share/icons/hicolor are reduced.

This does not cause actual issue since it is masked by pixmaps. But it should be fixed.

Version: 0.50.4
Distribution AppImage