IN_BADCLASS: fix macro to actually work

Commit 65cab850 ("net: Allow class-e address assignment via ifconfig
ioctl") modified the IN_BADCLASS macro a bit, but unfortunatly one too
many '(' characters were added to the line, making any code that used
it, not build properly.

Also, the macro now compares an unsigned with a signed value, which
isn't ok, so fix that up by making both types match properly.

Reported-by: Christopher Ferris <cferris@google.com>
Fixes: 65cab850 ("net: Allow class-e address assignment via ifconfig ioctl")
Cc: Dave Taht <dave.taht@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>