/usr/lib/x86_64-linux-gnu/libOgreRTShaderSystem.so is in libogre-1.8-dev 1.8.1+dfsg-0ubuntu3.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libOgreRTShaderSystem.so.1.8.1
/usr/lib/x86_64-linux-gnu/libOgreRTShaderSystem.so.1.8.1