If lib32symlinks contains plain library names without a path as in
the case of glibc (lib32symlinks="ld-linux.so.2") the expression
${f%/*} is not empty, but returns the basename.
Handle that case by verifying that ${f%/*} is different from ${f}.
Signed-off-by: Jürgen Buchmüller <pullmoll@t-online.de>