4.15.0-24.26) is not available, but a newer one is (4.15.0-46.49). We redirected you there.
/usr/mipsel-linux-gnu/lib32/ld.so.1 is in libc6-mipsn32-mipsel-cross 2.27-3ubuntu1cross1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/mipsel-linux-gnu/lib32/ld-2.27.so