nbd: update to 3.27.0

- new version
- move from sourceforge to github
- add gnutls library

-  fix compilation warning, by removing CFLAGS addition:
```
    <command-line>: warning: "PROG_NAME" redefined
    <command-line>: note: this is the location of the previous definition
```

- fix compilation by adding libnl3 which is detected by configure script
  and defines macros modifying the code. Error was:
```
    nbd-client.c: In function 'main':
    nbd-client.c:1723:32: error: implicit declaration of function 'persist_mode_main' [-Wimplicit-function-declaration]
     1723 |                         return persist_mode_main(index, sockfds, flags);
          |                                ^~~~~~~~~~~~~~~~~
```

NETLINK-related compilation problem reported upstream, with a proposed fix:
NetworkBlockDevice/nbd#183

Author: vincele

srcpkgs/nbd/template

@@ -1,24 +1,22 @@
 # Template file for 'nbd'
 pkgname=nbd
-version=3.24
+version=3.27.0
 revision=1
 build_style=gnu-configure
 configure_args="--enable-syslog"
 hostmakedepends="pkg-config bison"
-makedepends="libglib-devel"
+makedepends="libglib-devel libnl3-devel gnutls-devel"
 short_desc="Network Block Device utilities"
 maintainer="Orphaned <orphan@voidlinux.org>"
 license="GPL-2.0-or-later"
 homepage="https://nbd.sourceforge.io/"
-distfiles="${SOURCEFORGE_SITE}/nbd/nbd-${version}.tar.gz"
-checksum=a771022599525fd4f5c17c7b1c88696a91927c227e770425a55f67a7384441b6
+distfiles="https://github.com/NetworkBlockDevice/nbd/releases/download/nbd-${version}/nbd-${version}.tar.xz"
+checksum=422a02adcdbab01c622307c6babeda5c84ca6c6f2d4e0b29936e6ae9b6a7662f
 
 system_accounts="nbd"
 nbd_homedir="/var/chroot"
 conf_files="/etc/nbd-server/config"
 
-CFLAGS+="-DPROG_NAME='\"nbd-client\"'"
-
 post_configure() {
 	# skip systemd unit
 	vsed -e '/^SUBDIRS =/s/systemd//' -i Makefile