bnx2: Fix Sparse warnings

This patch will fix the following sparse warnings:

/home/benli/sparse/bnx2.c:297:8: warning: symbol 'val' shadows an earlier one
/home/benli/sparse/bnx2.c:286:60: originally declared here
/home/benli/sparse/bnx2.c:7461:7: warning: symbol 'i' shadows an earlier one
/home/benli/sparse/bnx2.c:7265:10: originally declared here

Signed-off-by: Benjamin Li <benli@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>