zink: request texcoord replace lowering

We don't actually support point-sprites by texcoord replacement, so let's
remove that cap. This allows gallium to automatically lower this to the
PNTC varying instead, which we do support.

Reviewed-by: Eric Anholt <eric@anholt.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6473>

src/gallium/drivers/zink/zink_screen.c

@@ -142,9 +142,6 @@ zink_get_param(struct pipe_screen *pscreen, enum pipe_cap param)
          return 0;
       return screen->info.props.limits.maxFragmentDualSrcAttachments;
 
-   case PIPE_CAP_POINT_SPRITE:
-      return 1;
-
    case PIPE_CAP_MAX_RENDER_TARGETS:
       return screen->info.props.limits.maxColorAttachments;