bonding: fix const in options processing

This is a fixup patch to resolve issues with const from my earlier patch.
Make all the setter functions use const on input parameter.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --cc drivers/net/bonding/bond_options.c
Simple merge

diff --cc drivers/net/bonding/bond_options.h
Simple merge

diff --cc drivers/net/bonding/bond_procfs.c
Simple merge