[netdrvr] ewrk3: correct card detection bug

[netdrvr] ewrk3: correct card detection bug

Arwin Vosselman pointed out:
> The ewrk3-driver doesn't function with 2.6.16-kernels (used 2.6.16.41 for
> my tests). Cards will never be detected due to this bug.
>
> drivers/net/ewrks3.c:
> Line 417 reads:
>
> if (nicsr == (CSR_TXD | CSR_RXD))
>
> that should be:
>
> if (nicsr != (CSR_TXD | CSR_RXD))
>
> Comparison with the same line in v2.4 shows why:
>
> 2.4:
> if (nicsr == (CSR_TXD | CSR_RXD)){
>
> blah, blah
> ==========
> 2.6:
> if (nicsr == (CSR_TXD | CSR_RXD))
>     return -ENXIO;
>
> blah, blah
> ==========
>
> blah,blah will not, but should, be executed in 2.6 with a card being present.
>
> The fix mentioned above solves this bug.

Signed-off-by: Jeff Garzik <jeff@garzik.org>