radv: disable 64-bit color attachments

radv: disable 64-bit color attachments

These work in some circumstances (dEQP-VK.spirv_assembly.instruction.graphics.16bit_storage.input_output_float_16_to_64.scalar9_tessc),
but I'm not sure if they work in all, blending certainly doesn't work and
this probably wasn't intended in the first place.

Signed-off-by: Rhys Perry <pendingchaos02@gmail.com>
Reviewed-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
Fixes: 01bd012edd20 ("amd: fix 64-bit integer color image clears")
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/24400>