bna: Staticize local functions

bna_rx_sm_stop_wait_entry(), bna_rx_sm_rxf_stop_wait_entry(),
bna_rx_sm_started_entry(), bna_rx_sm_cleanup_wait_entry(),
and bna_rx_sm_cleanup_wait() are used only in this file.
Fix the following sparse warnings:

drivers/net/ethernet/brocade/bna/bna_tx_rx.c:1423:1: warning: symbol 'bna_rx_sm_stop_wait_entry' was not declared. Should it be
static?
drivers/net/ethernet/brocade/bna/bna_tx_rx.c:1476:1: warning: symbol 'bna_rx_sm_rxf_stop_wait_entry' was not declared. Should it be
static?
drivers/net/ethernet/brocade/bna/bna_tx_rx.c:1532:1: warning: symbol 'bna_rx_sm_started_entry' was not declared. Should it be
static?
drivers/net/ethernet/brocade/bna/bna_tx_rx.c:1597:1: warning: symbol 'bna_rx_sm_cleanup_wait_entry' was not declared. Should it be
static?
drivers/net/ethernet/brocade/bna/bna_tx_rx.c:1602:1: warning: symbol 'bna_rx_sm_cleanup_wait' was not declared. Should it be static?

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: David S. Miller <davem@davemloft.net>