ice: use local for consistency

Do a minor refactor on ice_vsi_rebuild to use a local
variable to store vsi->type.

Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: Tony Brelinski <tonyx.brelinski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>