agx: Don't wait at the end of the shader

This is totally pointless. This saves some waits at the ends of compute kernels (waiting for stores to complete before terminating the thread). I don't know how much this would matter for performance, since the hardware may have to do these waits internally, but it makes the generated code less silly which is always nice.

Signed-off-by: Alyssa Rosenzweig alyssa@rosenzweig.io