ixgbe: Clear I2C destination location

Clear the destination location for I2C data initially so that
the received data will not be affected by previous attempts.
This could have returned wrong data in certain retry sequences.

Signed-off-by: Mark Rustad <mark.d.rustad@intel.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>