Cairo-dock-core's main CMakeLists.txt assumes that CMAKE_INTALL_LIBDIR
is a relative path, even though cmake's docs state that both relative
and absolute paths should be okay. If we specify a relative path, as
we do since commit 571db28a3d ("termux_step_configure_cmake: Revert
CMAKE_INSTALL_LIBDIR old behaviour changed in 2af00064"), then the
files are installed to $PREFIX/$PREFIX/lib instead of $PREFIX/lib.
Fixes: termux/termux-packages#11668