ice: Don't call ice_cfg_itr() for SR-IOV

ice_cfg_itr() sets the ITR granularity and default ITR values for the
PF's interrupt vectors. For VF's this will be done in the AVF driver
flow. Fix this by not calling ice_cfg_itr() for SR-IOV.

Signed-off-by: Brett Creeley <brett.creeley@intel.com>
Signed-off-by: Anirudh Venkataramanan <anirudh.venkataramanan@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>