gianfar: Fix build with CONFIG_PM=y

commit fba4ed03 ("gianfar: Add Multiple
Queue Support") introduced the following build failure:

  CC      gianfar.o
gianfar.c: In function 'gfar_restore':
gianfar.c:1249: error: request for member 'napi' in something not a structure or union

This patch fixes the issue.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: David S. Miller <davem@davemloft.net>