graphics/gstreamer*-plugins-opencv: fix fallout form OpenCV-4.5.1 upgrade

• graphics/gstreamer-plugins-opencv: disabled, as it uses the no longer shipped OpenCV-1.0 API
• graphics/gstreamer1-plugins-opencv: fix the configure script to not only look for OpenCV4 <= 4.2.0 => this will be properly fixed with the next upgrade of gstreamer when switching to the meson build system.

PR: 253118
Submitted by: VVD <vvd@unislabs.com>
Reported by: rhurlin, fluffy, VVD <vvd@unislabs.com>