Include FSR 2.0 in the upscaling module

AMD finally published the source code of FSR 2.0 (their open-source temporal option for upscaling). Since FSR 1.0 is already included in the upscaling module, this should be added as well for completeness. Also a temporal solution for projects with motion vectors would be neat (potentially useful for the motion-blur demo).

FSR 2.0 code: https://github.com/GPUOpen-Effects/FidelityFX-FSR2