This delta addresses some users experiencing watchdogs under load with
    the last driver version. I suspect sheduling to be at the bottom of it,
    but this version fixes it by:
    	- Making FAST interrupt handling off by default, if you want
    	to use it #define EM_FAST_IRQ in the Makefile.
    	- Add dual locks, one for the TX subsystem, the other CORE
    	for things like init and interface managment.
    	- Add cleaner MSI/X setup code.
    	- If using FAST interrupts there is now a mechanism in the
    	watchdog routine to kick off TX cleanups if they have not
    	been scheduled.
    
    I think everyone will be happier with this change.