Merge branch 'bonding-cleanup-header-file-and-error-msgs'

Jonathan Toppins says:

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bonding: cleanup header file and error msgs

Two small patches removing unreferenced symbols and unifying error
messages across netlink and printk.
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Link: https://lore.kernel.org/r/cover.1628650079.git.jtoppins@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>