bna: remove paused from bna_rx_config and flags from bna_rxf

The bna_rx_config struct member paused can be removed as it is never
written and as it cannot have non-zero value the bna_rxf struct member
flags also cannot have BNA_RXF_F_PAUSED value and is always zero.
So the flags member can be removed as well as bna_rxf_flags enum and
the code-paths that needs to have non-zero bna_rxf->flags.
This clean-up makes bna_rxf_sm_paused state unsed and can be also removed.

Signed-off-by: David S. Miller <davem@davemloft.net>