qlge: Get rid of 'default' rx_ring type.

Currently we have three types of RX rings.

1) Default ring - services rx_ring for broadcast/multicast, handles
firmware events, and errors.

2) TX completion ring - handles only outbound completions.

3) RSS ring - handles only inbound completions.

This patch gets rid of the default ring type and moves it's functionality
into the first RSS ring.  This makes better use of MSIX vectors since
they are a limited resource on some platforms.

Signed-off-by: Ron Mercer <ron.mercer@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>