Fix typo in manpage

Link: https://savannah.gnu.org/bugs/?66365

Fixes: #145

…abilities

On non-Linux systems, bfs_check_capabilities always returned -1, so
cpath_has_capabilities would always return true. If bfs was called with
an LS_COLORS containing the `ca` statement, e.g. `ca=30;41`, bfs would
color ALL the files.  While including the `ca` statement in LS_COLORS
on non-Linux systems is unusual, this is not an error and is a valid
use-case (e.g. Using GNU ls or lsd).

Fixes: 1520d4d ("color: Don't color files like directories on ENOTDIR")

Fix bfs coloring all files as if they had a capability, on non-Linux systems