s2io: fixing DBG_PRINT() macro

Patch 9e39f7c5 changed the
DBG_PRINT() macro and the if clause was wrongly changed. It means
that currently all the DBG_PRINT are being printed, flooding the
kernel log buffer with things like:

s2io: eth6: Next block at: c0000000b9c90000
s2io: eth6: In Neterion Tx routine

Signed-off-by: Breno Leitao <leitao@linux.vnet.ibm.com>
Acked-by: Sreenivasa Honnur <Sreenivasa.Honnur@neterion.com>
Signed-off-by: David S. Miller <davem@davemloft.net>