[TULIP] DMFE: Fix SROM parsing regression.

Changeset 16b110c3fd760620b4a787db6ed512fe531ab1b5 (dmfe warning fix)
bothed up the offsets read from the SROM so that it doesn't read the
same datums it used to.

The change made transformations like turning:

	"srom + 34"

into

	"(__le32 *)srom + 34/4"

which doesn't work because 4 does not divide evenly
into 34 so we're using a different pointer offset
than in the original code.

I've changed theses cases in dmfe_parse_srom() to
consistently use "(type *)(srom + offset)" preserving
the offsets from the original code.

Signed-off-by: David S. Miller <davem@davemloft.net>