shell/util: Validate create_pixbuf_from_data() parameters

shell/util: Validate create_pixbuf_from_data() parameters

The function is used to create a pixbuf from image data for
a search provider or notification client.

Without validation, a malicious client can provide a data array that
is smaller than the size required by the passed image parameters,
which will eventually result in out-of-bound reads.

Closes: https://gitlab.gnome.org/GNOME/gnome-shell/-/issues/9365
Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/4418>
(cherry picked from commit 8a3f208d0123b4831b1a4ba1040acc4f9091d465)