bonding: change bond_create_proc_entry() to return void

The function bond_create_proc_entry is currently of type int.

Two versions of this function exist:

The one in the ifdef CONFIG_PROC_FS branch always return 0.
The one in the else branch (which is empty) return nothing.

When CONFIG_PROC_FS is undef, this cause the following warning:

drivers/net/bonding/bond_main.c: In function `bond_create_proc_entry':
drivers/net/bonding/bond_main.c:3393: warning: control reaches end of
non-void function

No caller of this function use the returned value.

So change the returned type from int to void and remove the
useless return 0; .

Signed-off-by: Nicolas de Pesloüan <nicolas.2p.debian@free.fr>
Reported-by: Rakib Mullick <rakib.mullick@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>