Add the riscv64 page to the cluster management guide (UEFI + grub2 boot
path, discovery through mknb's grub2 network configurations, stateful and
stateless provisioning, the dependency picture for a management node on
riscv64, limitations), list riscv64 in the node object attributes and in
the support matrices, add the architecture to the cross-build page for
stateless images, extend the grub2 install guide (and fix its swapped
x86_64/aarch64 file names), the uninstall package lists, the DHCP backend
validation matrix and the mknb/genimage man pages, and carry the riscv64
schema values into the generated nodetype, osimage, noderes, node and
group references.
Added documentation primarily for building the man pages locally
There is a requirement for pod2rst
Modified the create_man_pages script to allow for local perl
module path