iavf: Disallow changing rx/tx-frames and rx/tx-frames-irq

Remove from supported_coalesce_params ETHTOOL_COALESCE_MAX_FRAMES
and ETHTOOL_COALESCE_MAX_FRAMES_IRQ. As tx-frames-irq allowed
user to change budget for iavf_clean_tx_irq, remove work_limit
and use define for budget.

Without this patch there would be possibility to change rx/tx-frames
and rx/tx-frames-irq, which for rx/tx-frames did nothing, while for
rx/tx-frames-irq it changed rx/tx-frames and only changed budget
for cleaning NAPI poll.

Fixes: fbb7ddfe ("i40evf: core ethtool functionality")
Signed-off-by: Przemyslaw Patynowski <przemyslawx.patynowski@intel.com>
Signed-off-by: Jun Zhang <xuejun.zhang@intel.com>
Tested-by: Marek Szlosek <marek.szlosek@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>