myri10ge: add multislices support

Add multi-slice/MSI-X support. By default, a single slice
(and the normal firmware) are used.  To enable msi-x, multi-slice
mode, one must load the driver with myri10ge_max_slices set to
either -1, or something larger than 1.

Signed-off-by: Brice Goglin <[email protected]>
Signed-off-by: Andrew Gallatin <[email protected]>
Signed-off-by: Jeff Garzik <[email protected]>

Author: Brice Goglin