meson: fix pylibfdt missing dependency on libfdt

The python library requires libfdt to build. This would intermittently
fail depending on what order targets compiled.

Signed-off-by: Brandon Maier <brandon.maier@collins.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

pylibfdt/meson.build

@@ -4,6 +4,7 @@ setup_py = [setup_py, '--quiet', '--top-builddir', meson.project_build_root()]
 custom_target(
   'pylibfdt',
   input: 'libfdt.i',
+  depends: libfdt,
   output: '_libfdt.so',
   command: [setup_py, 'build_ext', '--build-lib=' + meson.current_build_dir()],
   build_by_default: true,