freedreno: Fix assertion failures on GS/tess shaders with shader-db enabled.

freedreno: Fix assertion failures on GS/tess shaders with shader-db enabled.

We weren't filling in the tess mode of the key, or setting has_gs on GS
shaders, resulting in assertion failures when NIR intrinsics didn't get
lowered.

We have to make a guess at prim mode for TCS, but it should be better to
have some shader-db coverage than none, and it will avoid these failures
happening when we start precompiling shaders.

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4562>