radv: Fix CTS for and expose EXT_sample_locations on GFX10+
Collection of work to get EXT_sample_locations to pass CTS on GFX10+.
CTS passes for: resolve, image_clearing and sample_locations on RX 7900XTX.
Collection of work to get EXT_sample_locations to pass CTS on GFX10+.
CTS passes for: resolve, image_clearing and sample_locations on RX 7900XTX.