gl/viv-fb: fix gl plugin hang when run with viv-fb backend

gl/viv-fb: fix gl plugin hang when run with viv-fb backend

below commit change the window resize thread and cause viv-fb backend
hang, need move resize code after window->open is called. Otherwise,
the resize message will send to a thread that not start running and
window resize call will waiting forever.

Commit:        b887db1efe816c0c28b60a6842fa9005a26c1502
glwindow: fix racy resize updates

Take locks around resize handling and marshall all resizes to the
windowing thread by default.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-base/-/merge_requests/1195>