vrend: Handle FakeMSAA textures consistently
If nr_samples is 1 we allocate textures as MULTISAMPLE, so we also need to handle the textures in later use as a multisample texture. In addition, on GLES blits to a multisample texture are not allowed as target, and we must use the GL blit fallback for all texture types.
Edited by Gert Wollny