panfrost: The texture descriptor has a pointer to a trampoline

Not to the texture itself, and can have a stride right after for linear
textures.

Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Reviewed-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Part-of: <mesa/mesa!4680>
27 jobs for !4680 with bifrost-3 in 19 minutes and 56 seconds (queued for 2 seconds)
merge request