package/glslsandbox-player: bump to version v2021.08.24

package/glslsandbox-player: bump to version v2021.08.24

Changes since v2019.08.23:
- Some X11 improvements (fullscreen support)
- New EGL driver debug messages
- Wayland improvements (xdg_shell, fullscreen support)
- KMS/DRM/GBM improvements (use drmGetDevices2())
- Use eglGetPlatformDisplay() if available
- New "nullws" native windowing system
- License hash changed due to copyright date update

Fixes:
http://autobuild.buildroot.net/results/a950e90d5f8405534566df5c7a8875c293cf8845

Signed-off-by: Julien Olivain <ju.o@free.fr>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>