tg3: Improve internal resource allocations

The 5717 and the 57765 have more resources at their disposal internally.
This patch tunes the driver to get better performance.  The adjustments
made here only apply to the 57765 and 5717 asic revs.

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