radv: Decompress DCC when the image format is not allowed for buffers.

Otherwise the buffer loads/stores in the bufimage meta operations fail.

If we decompress DCC then we can use the "canonical" format compatible
with the not-supported format.

CC: <mesa-stable@lists.freedesktop.org>
Reviewed-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
(cherry picked from commit 41075909)