libnfsidmap-dev has been integrated into nfs-utils since 2.2.1

Fixes: #8487

Had demote some -Werror flags to warnings due to build failing.

enabled svcgssd build flag, applied patch from gentoo to make it
build and wrote another patch to fix segfaults, because musl
returns -1 for sysconf(_SC_GETGR_R_SIZE_MAX), which was not handled
at all, thus allocating a smaller buffer than needed.

idmapd requires CONFIG_DNOTIFY, which is not enabled in
linux-vanilla or linux-hardened. This is fixed by applying this
patch (https://patchwork.kernel.org/patch/9802949/) by Alan Swanson
which uses INOTIFY instead.

[TT: bump pkgrel, use mbox version of patch]

This seems the defaulf for gentoo and debian.

use patch series sent to linux-nfs mailing list, and add one more
patch to address accessing /proc/net/rpc.

There are 2 different versions of basename and apparently the gnu
version from string.h segfault. We include libgen.h so we get the
posix version

iupstream appear to have modified source package

fixes #1609

We currently don't support gssd.

ref #1609