Revert "radv: Don't store buffer references in the descriptor set."

Revert "radv: Don't store buffer references in the descriptor set."

In order to reduce a performance regression introduced by
4b13fe55a4 ("radv: Keep a global BO list for VkMemory."),
we are going to maintain two different paths.

One when VK_EXT_descriptor_indexing is enabled by the
application because we need to have a global BO list, and
one (the old one) when it's not enabled.

With Talos on Polaris, the global BO list reduces performance
by 10% which is too much for me.

This reverts commit ab6cadd3ecc7fbdd9079808b407674e0b19c52f0.
Reviewed-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>