zink: reset PIPE_CAP_ACCELERATED when cpu soft rendering

This field can be used to disable some unsupport/unproper hardware
acceleration. Reset it when zink is runing on cpu rendering.

Reviewed-by: Mike Blumenkrantz <michael.blumenkrantz@gmail.com>
Signed-off-by: Qiang Yu <yuq825@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/15765>

src/gallium/drivers/zink/zink_screen.c

@@ -672,7 +672,7 @@ zink_get_param(struct pipe_screen *pscreen, enum pipe_cap param)
       return screen->info.props.deviceID;
 
    case PIPE_CAP_ACCELERATED:
-      return 1;
+      return !screen->is_cpu;
    case PIPE_CAP_VIDEO_MEMORY:
       return get_video_mem(screen) >> 20;
    case PIPE_CAP_UMA: