w1: Fixup source file headers

Remove filename from file, this is not done anymore as it doesn't
add anything and usually is incorrect as filename change often.

Also shorten the GPL to the more common address-less version and
remove excess white-space.

Signed-off-by: Andrew F. Davis <afd@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>