Good day.

===
gusextreme: port to isa_bus infrastructure

Signed-off-by: Rene Herman <rene.herman@gmail.com>
===

Straightforward combination of es1688 and gusclassic. The legacy create 
has been divided into one es1688 and one gus_card function really only 
due to the:

        if (gf1_port[n] < 0)
                gf1_port[n] = es1688->port + 0x20;

line that wants to be in between -- this should be done even when we 
weren't doing legacy probing for es1688 so wants to be in probe() 
itself. This does change the order in which resources are requested by 
the code, bus that's actually a good thing. The gusextreme included the 
es1688 specifically for soundblaster compatibility, meaning the standard 
port=0220,irq=5,dma=1 soundblaster triple should preferably be assigned 
to it as happens now; in the old situation, GF1 got IRQ5. GF1 now first 
probes for the IRQs the es1688 can't use anyway ...

Has been tested and works fine, if not for one small bug also present in 
the original -- see next message.

Rene.