wimax: make functions local

Make wimax variables and functions local if possible.
Compile tested only.

This also removes a couple of unused EXPORT_SYMBOL.
If this breaks some out of tree code, please fix that
by putting the code in the kernel tree.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>