Currently there is no support for dynamic interrupt moderation. This patch adds some initial code to support this. The following changes were made: 1. Currently we are using multiple members to store the interrupt granularity (itr_gran_25/50/100/200). This is not necessary because we can query the device to determine what the interrupt granularity should be set to, done by a new function ice_get_itr_intrl_gran. 2. Added intrl to ice_q_vector structure to support interrupt rate limiting. 3. Added the function ice_intrl_usecs_to_reg for converting to a value in usecs that the device understands. 4. Added call to write to the GLINT_RATE register. Disable intrl by default for now. 5. Changed rx/tx_itr_setting to itr_setting because having both seems redundant because a ring is either Tx or Rx. 6. Initialize itr_setting for both Tx/Rx rings in ice_vsi_alloc_rings() 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>