Fix obvious editor mishap in previous

Obliterate bogus $@ usage.

While here, fix some quoting, change some style, and attempt
to properly handle wedge names with embedded newlines, and those
that end with a '/' character (not particularly happy with the
solution to that last one, but it is better than it was).

Is there a reason that characters that need encoding in wedge names
(white space, and more) are encoded as %%XX (XX is the hex value of
the char - but 2 % chars? Why?). That remains unchanged, but as
the script already relied upon sh's $'...' quoting, I think we can rely
upon printf as well, so replace the old (very elegant, but slow) encoding
function with a much simpler one (does the same thing).

Also replace calls to dirname.

Remove need for awk/sed/readlink tools.

Avoid error message when /dev/wedges doesn't exist yet.

safely update existing wedge links

At startup, instead of doing run-hooks for each device, call run-hooks
once with a list of all found devices. This lets us batch calls to MAKEDEV
which results in a noticeable improvement in Raspberry Pi boot time.

Run the initial device enumeration hooks before detaching from the foreground,
ensuring that any required devices have been created before the rc.d script
exits.

branches: 1.1.2; 1.1.6; 1.1.12;
Provide a script for devpubd(8) that creates symlinks for each dk(4)
device under /dev/wedges so that you can access them by name.