panfrost: Add AFBC packing support for RG formats

Only a matter of enabling it as packing itself works the same no
matter the number of components.

Signed-off-by: Louis-Francis Ratté-Boulianne <lfrb@collabora.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Erik Faye-Lund <erik.faye-lund@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/27471>

src/panfrost/lib/pan_afbc.c

@@ -185,9 +185,5 @@ panfrost_afbc_can_pack(enum pipe_format format)
 {
    const struct util_format_description *desc = util_format_description(format);
 
-   if (desc->nr_channels != 1 && desc->nr_channels != 3 &&
-       desc->nr_channels != 4)
-      return false;
-
    return desc->colorspace == UTIL_FORMAT_COLORSPACE_RGB;
 }