ixgbe: fix function-like macro, remove semicolon

This patch removes the semicolon from the end of the do-while(0)
construct in two function-like macros.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>