ice: Adjust scheduler default BW weight

By default the queues are configured in legacy mode. The default
BW settings for legacy/advanced modes are different. The existing
code was using the advanced mode default value of 1 which was
incorrect. This caused the unbalanced BW sharing among siblings.
The recommended default value is applied.

Signed-off-by: Tarun Singh <tarun.k.singh@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>