Install pyrealsense2 .so and __init__.py

[eufrizz]

Fix for python bindings, issue https://github.com/IntelRealSense/librealsense/issues/13080 , where pyrealsense2 is not installed when built from source. Added:

• install rule for libraries
• install rule for __init__.py which was necessary for python to find the module

The first was added in an else statement because the installation is done when pybackend2 is used

At make install, you now see these extra lines:

-- Installing: /usr/lib/python3/dist-packages/pyrealsense2/pyrealsense2.cpython-310-aarch64-linux-gnu.so.2.56.0
-- Installing: /usr/lib/python3/dist-packages/pyrealsense2/pyrealsense2.cpython-310-aarch64-linux-gnu.so.2.56
-- Set runtime path of "/usr/lib/python3/dist-packages/pyrealsense2/pyrealsense2.cpython-310-aarch64-linux-gnu.so.2.56.0" to ""
-- Installing: /usr/lib/python3/dist-packages/pyrealsense2/pyrealsense2.cpython-310-aarch64-linux-gnu.so
...
-- Up-to-date: /usr/lib/python3/dist-packages/pyrealsense2/__init__.py

Other related issues:

https://github.com/IntelRealSense/librealsense/issues/10635 https://github.com/IntelRealSense/librealsense/issues/6449 https://github.com/IntelRealSense/librealsense/issues/6964#issuecomment-707501049 https://github.com/IntelRealSense/librealsense/issues/12894 https://github.com/IntelRealSense/librealsense/issues/3062 and more...

[sysrsbuild]

Can one of the admins verify this patch?

[Nir-Az]

Thanks!