Before this change the function `__fish_print_filesystems` would print
an error message about an empty wildcard match for the pattern
`$PATH/mount.*`, if the current operating system does not include any
helper binaries for the command `mount`. An example for such an OS is
the current version of macOS (version 10.12).
I hate doing this but I am tired of touching a fish script as part of
some change and having `make style` radically change it. Which makes
editing fish scripts more painful than it needs to be. It is time to do
a wholesale reformatting of these scripts to conform to the documented
style as implemented by the `fish_indent` program.
