backend-rdp: work around unresolved symbols

This is preparation for disallowing unresolved symbols project-wide.

This is a temporary fix that should be reverted and fixed properly later.

/usr/bin/ld: libweston/backend-rdp/13a5658@@rdp-backend@sha/rdp.c.o: in function `rdp_peer_context_new':
/home/pq/build/weston-meson/../../git/weston/libweston/backend-rdp/rdp.c:748: undefined reference to `Stream_New'
/usr/bin/ld: libweston/backend-rdp/13a5658@@rdp-backend@sha/rdp.c.o: in function `rdp_peer_context_free':
/home/pq/build/weston-meson/../../git/weston/libweston/backend-rdp/rdp.c:781: undefined reference to `Stream_Free'
/usr/bin/ld: libweston/backend-rdp/13a5658@@rdp-backend@sha/rdp.c.o: in function `xf_input_keyboard_event':
/home/pq/build/weston-meson/../../git/weston/libweston/backend-rdp/rdp.c:1220: undefined reference to `GetVirtualKeyCodeFromVirtualScanCode'
/usr/bin/ld: /home/pq/build/weston-meson/../../git/weston/libweston/backend-rdp/rdp.c:1224: undefined reference to `GetKeycodeFromVirtualKeyCode'
/usr/bin/ld: libweston/backend-rdp/13a5658@@rdp-backend@sha/rdp.c.o: in function `weston_backend_init':
/home/pq/build/weston-meson/../../git/weston/libweston/backend-rdp/rdp.c:1469: undefined reference to `winpr_InitializeSSL'

See also #262

Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.com>

libweston/backend-rdp/meson.build

@@ -31,6 +31,7 @@ plugin_rdp = shared_library(
 	include_directories: common_inc,
 	dependencies: deps_rdp,
 	name_prefix: '',
+	override_options: [ 'b_lundef=false' ],
 	install: true,
 	install_dir: dir_module_libweston
 )