[RFC PATCH] migration: Add missing dependency on GNUTLS

["Philippe Mathieu-Daudé" <f4bug@amsat.org>]

Commit 7de2e856533 made migration/qemu-file-channel.c include
"io/channel-tls.h" but forgot to add the new GNUTLS dependency
on Meson, leading to build failure on OSX:

  [2/35] Compiling C object libmigration.fa.p/migration_qemu-file-channel.c.o
  FAILED: libmigration.fa.p/migration_qemu-file-channel.c.o
  cc -Ilibmigration.fa.p -I. -I.. -Iqapi [ ... ] -o libmigration.fa.p/migration_qemu-file-channel.c.o -c ../migration/qemu-file-channel.c
  In file included from ../migration/qemu-file-channel.c:29:
  In file included from include/io/channel-tls.h:26:
  In file included from include/crypto/tlssession.h:24:
  include/crypto/tlscreds.h:28:10: fatal error: 'gnutls/gnutls.h' file not found
  #include <gnutls/gnutls.h>
           ^~~~~~~~~~~~~~~~~
  1 error generated.

Reported-by: Stefan Weil <sw@weilnetz.de>
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/407
Fixes: 7de2e856533 ("yank: Unregister function when using TLS migration")
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
---
RFC: Not tested on OSX. Stefan, do you know why this isn't covered
     on Cirrus-CI?  https://cirrus-ci.com/build/4876003651616768
---
 migration/meson.build | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/migration/meson.build b/migration/meson.build
index f8714dcb154..5b5a3f7b337 100644
--- a/migration/meson.build
+++ b/migration/meson.build
@@ -8,7 +8,7 @@
   'qemu-file.c',
   'yank_functions.c',
 )
-softmmu_ss.add(migration_files)
+softmmu_ss.add(migration_files, gnutls)
 
 softmmu_ss.add(files(
   'block-dirty-bitmap.c',
-- 
2.31.1