at-spi2-core: add at-spi2-atk to CVE_PRODUCT

Commit ad605662 ("at-spi2-core: upgrade 2.44.1 -> 2.46.0") dropped
the at-spi2-atk recipe, because it was merged into at-spi2-core upstream
[1]. The PROVIDES variable was changed to also include at-spi2-atk, but
not CVE_PRODUCT.

[1]: https://gitlab.gnome.org/GNOME/at-spi2-core/-/merge_requests/78



Signed-off-by: Emil Kronborg <emil.kronborg@protonmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>