routing:
- style(9) cleanup -- white space, braces, etc.
- Make include guards consistent with our more general naming
convention.
- Rearrange and complete forward structure declarations in at_extern.h,
remove testing of guards of various other include files to protect
function declarations.
This leaves an ifdef _KERNEL in at_var.h, but from inspection it seems
likely that this file is not actually safe for inclusion in user space
still. However, since it's not included from within src/ so this does
not appear to be an issue (ifconfig, etc, have migrated to the generic
cross-protocol ioctls for address operations).
Kernel Appletalk protocol support
both CAP and netatalk can make use of this..
still needs some owrk but it seemd the right tiime to commit it
so other can experiment.
