images/arch: Avoid losing p11-kit-client.so by accident

The libp11-kit package was added to the arch-toolbox image to ensure the
presence of p11-kit-client.so.  Currently, the package is already pulled
in by various dependencies, like the gnutls and p11-kit packages.
Therefore, it doesn't increase the size of the base image, but serves as
a safeguard against any inadvertent changes.

A subsequent commit will use this to give Toolbx containers access to
the certificates from certificate authorities on the host.  This commit
was kept separate from the changes to toolbox(1) to ensure that the
arch-toolbox image is ready before that happens.

https://github.com/containers/toolbox/issues/626

images/arch/extra-packages

@@ -4,6 +4,7 @@ flatpak-xdg-utils
 git
 gnupg
 keyutils
+libp11-kit
 lsof
 man-db
 man-pages