number of queued packets in watchdog timeout handler. If there are
no queued packets just print a informational message and return
without resetting controller. Also fix to invoke correct Tx
completion handler as 3C905B needs different handler.
Previously it used to clear the flag only when the transmit queue
is empty which may slow down Tx performance.
While I'm here check whether driver is running and whether we can
queue more packets in if_start handler. This fixes occasional
watchdog timeouts.
Reported by: xer < xernet <> hotmail dot it >
Tested by: xer < xernet <> hotmail dot it >
