ixgbe: Reduce I2C retry count on X550 devices

A retry count of 10 is likely to run into problems on X550 devices that
have to detect and reset unresponsive CS4227 devices. So, reduce the I2C
retry count to 3 for X550 and above. This should avoid any possible
regressions in existing devices.

Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>