main/{cifs,nfs}-utils: configure with request-key support

The Linux Kernel documentation[0] suggests that NFS will first attempt to call /sbin/request-key to direct ID mapping upcalls to /usr/sbin/nfsidmap. When a user installs 'nfs-utils' on a client system to mount an NFS share, /sbin/request-key ideally should be preconfigured with the sane default that is recommended by the Linux Kernel.

This patch pre-configures NFS and CIFS to work out of the box with request-key.

[0] https://www.kernel.org/doc/html/latest/admin-guide/nfs/nfs-idmapper.html