net: socionext: Demote non-compliant kernel-doc headers

Fixes the following W=1 kernel build warning(s):

 drivers/net/ethernet/socionext/sni_ave.c:28: warning: expecting prototype for sni_ave.c(). Prototype was for AVE_IDR() instead

Signed-off-by: Yang Shen <shenyang39@huawei.com>
Reviewed-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Signed-off-by: David S. Miller <davem@davemloft.net>